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Class T- S \ $ 8 O 

Book iSr^ 

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COPYRIGHT DEPOSIT. 



I 

Goodrich Employees Reading Course 
Volume V 



RUBBER IN 
INDUSTRY 

A STORY OF THE DEVELOPMENT 
MANUFACTURE AND USES OF 

RUBBER BELTING— HOSE— MOLDED GOODS- 
PACKINGS — FLOOR COVERINGS — MISCELLA- 
NEOUS RUBBER ARTICLES AND RUBBER INSU- 
LATED WIRE. 



?£6 

2<m 




WRITTEN IN 
The Training Division, Sales Personnel Dept. 

OF 

The B. F. Goodrich Rubber Co. 

Akron, Ohio 

1918 






%o 



CoPYRKiHJ, 1919, BY 

The B. F. GoqpMcfc Rubber Company 
*1919 




JUL -7 1919 



'©CI.A529101 



Preface 



When employed in connection with rubber manufac- 
turing, the term, Mechanical Goods, embraces that 
group of articles which are used in conjunction with 
the construction of other things and regardless . of 
whether these be a part of the finished product itself 
or accessory to the equipment employed in its manu- 
facture, the fact remains the same. By way of illus- 
tration — the radiator hose 'of an automobile is an article 
falling into this category just as is the gigantic drive 
belt transmitting the force from the motor or steam 
engine to the machines shaping the parts of the car; 
or the little rubber disk used as a bumper behind the 
stateroom door of a Pullman car is just as much a 
mechanical item as is also the rubber tiling on the 
corridor floors of the car manufacturers' office building. 

Literally thousands of different purpose items come 
under this classification, which, for convenience in 
factory, office, and sales procedure, we group under the 
following general heads: Belting, Hose, Molded and 
Lathe Cut Goods, Packing, Matting, Tiling, Miscel- 
laneous Goods and Insulated Wire. The line of de- 
marcation between the divisions is, however, not very 
evident in places, and consequently, it must be under- 
stood by the reader that this classification is more for 
convenience than for absolute accuracy. 

We are treating the various articles under the standard 
headings adopted by most rubber goods manufacturers; 
which sectional method, we believe, will assist the reader 
to form a more logical mental outline of what is em- 
braced by the term "Mechanical Rubber Goods." Under 



these several sections we have again divided the discus- 
sion, using numerous sub-headings to further aid the 
classification and also to furnish a means for ready 
reference. 

More than this, it is our aim in telling the story of 
these Goodrich products to make the text not only 
vivid enough so that the reader cannot escape the fact 
that this division of our line is the result of a half cen- 
tury of development, brought about primarily to meet 
the needs of industrial growth; but likewise to show 
why this development is ever increasing with the grow- 
ing adaptability of rubber goods for use in connection 
with manufacturing. We offer this volume as an ele- 
mentary text book on Mechanical Rubber Goods with 
the belief that it will form a foundation around which 
may be built a fundamental knowledge of the history, 
varying uses, and methods of manufacture, together 
with marketing methods of these important divisions of 
Goodrich products. 

Mechanical Rubber Goods were the pioneer products 
of the B. F. Goodrich Company; hose being in fact the 
first creation. This first product, i.e., water hose, was 
made and marketed under the brand name, "White 
Anchor," a brand which subsequently became so famous 
for quality throughout the mechanical world that even 
after all these years, the name "White Anchor" is still 
synonymous with hose made of the finest of rubber and 
duck obtainable and it is true that not only does this 
product still represent the "last word" in quality, but 
of workmanship as well. Such is the foundation and 
character of the Goodrich Mechanical Rubber Goods 
line. 



Table of Contents 

CHAPTER ONE 
Rubber Belting 

History 1 

Characteristics of Rubber Belting 6 

The Manufacture of Belting 8 

Transmission Belts 14 

Conveyor Belts 20 

Belt Elevators 31 

Brands 36 

CHAPTER TWO 
Rubber Hose 

Definition 39 

Historical 40 

Characteristics of Rubber Hose 45 

The Manufacture of Rubber Hose 52 

The Uses of Hose 62 

CHAPTER THREE 
Molded and Lathe-Cut Rubber Goods 

Definition 64 

Historical 65 

The Manufacture of Molded and Lathe-Cut Goods _ _ 67 

The Use of Molded Goods 73 

CHAPTER FOUR 
Packings 

Introduction 84 

The Manufacture of Packing 87 

Characteristics of Packing 91 

Conclusion 93 



CHAPTER FIVE 
Rubber Floor Coverings 

Definition 95 

History 96 

Manufacture of Rubber Floor Coverings 97 

The Use of Rubber Floor Covering 102 

Care of Rubber Floor Coverings 103 

CHAPTER SIX 
Miscellaneous Articles 

Rubber Thread 105 

Rubber Rolls 107 

Deckle Straps 109 

Glazing or Channel Rubber 110 

CHAPTER SEVEN 
Marketing 

Selling___ 112 

Channels of Distribution 113 

Branch Stocks 114 

Guarantee 114 

CHAPTER EIGHT 

Electricity 

(Insulated Wire) 

Compendium 119 

What is Electricity? 120 

Nomenclature 120 

The Electric Battery— Volta 121 

Voltaic Battery 122 

Magnetism 1 22 

The Compass 122 

Artificial Magnets 122 

Polarity 123 

Value of Polarity 123 

Magnetic Force of Electric Current — Oersted 124 

Electro-Magnets 125 



Henry 125 

Faraday 125 

Modern Electricity 

The Telegraph 126 

The Dynamo and Motor 126 

Definitions of Electrical Terms 127 

Direct Current 128 

Alternating Current 128 

Circuit 128 

Volt — Ampere 128 

Resistance 129 

Volt 129 

Ohm 129 

Ampere 129 

Watt— Kilowatt 129 

Transmission of Electric Current 130 

Transformers _ 131 

Wireless Telegraphy 132 

The Primary Cell and Storage Battery 132 

The Primary or Voltaic Battery 133 

Commercial Batteries 134 

The Storage Battery 135 

Types 136 

The Nickel-Iron Storage Battery 136 

CHAPTER NINE 
Wire 

Conductors 138 

Resistance 139 

Copper 142 

Early Industry 143 

Prospecting 144 

Mining 144 

Stamping 145 

Smelting 146 

Electrolytic Refining 147 

"Pitch" 148 



Rolling Mills 148 

Wire Drawing 148 

Tinning 150 

Wire Gauges 150 

Circular Measure of Wire 151 

Stranded Wire 151 

Copper Wire Table 153 

CHAPTER TEN 
Insulation 

Copper 154 

Rubber 155 

Manufacturing 155 

Underwriter's Code 157 

Plain Rubber Covered 159 

Fabric Covered Wire 160 

Multiple Conductors 162 

Lead Covered Cable 163 

Tests 164 

The Use of Insulated Wire 166 

CHAPTER ELEVEN 
Marketing 

Selling 169 

Channels of Distribution 169 

Branch Stocks 171 



CHAPTER ONE 

Rubber Belting 

TTISTORY. Belting, not unlike many other scientific 
-*--*- mechanical appliances had a simple beginning; 
and though in its present multi-ramifications is used 
for conveying and elevating materials, polishing silver- 
ware, and handling pills it was first intended exclusively 
for the transmission of power. In order that we may brief- 
ly develop the history of power transmission it is first 
necessary for us to consider the origin of mechanical 
devices and mills which created the requirement for 
power drives. The early mechanical exigencies of pre- 
historic man were satisfied by the lever which was, no 
doubt, the first mechanical invention; and coming to 
us as a heritage, is still the most efficient of all me- 
chanical devices. The lever served to move stones, lift 
great weights, and to generally augment physical 
strength. It became a part of every implement and 
alone served all requirements until the invention of 
milling processes. 

Long before the dawn of history, cereals formed an 
important article of food for the human race. The first 
grain was gathered where it grew wild; but after the 
formation of the states large groups of individuals re- 
quired more cereal food than unassisted nature produced 
in a given district within reasonable bounds. Agricul- 
ture, therefore, was one of the earliest arts of civiliza- 
tion to be developed; and cereals were among the first 
of the agricultural products to receive cultivation. Inter- 



Rubber in Industry 

communication and community reasoning must have 
very early developed the fact that grain is much im- 
proved by grinding; both from the standpoint of masti- 
cation and flavor and therefore it is not unreasonable 
to suppose that the first milling process came soon after 
the cultivation of the soil. 

The earliest history we have, however, concerning 
the grinding of wheat or corn dates back only 6000 
years to the days of the Egyptian peoples. By 
them, breaking the grain into fragments by means of a 
mortar and pestle was all that was attempted in the 
beginning. But the second step in the development of 
milling was also taken several thousand years B.C. 
when two roughened grinding surfaces, between which 
the grain was reduced to powder, were substituted for 
the mortar and pestle. The use of upper and nether 
millstones for grinding grain, therefore, doubtless con- 
stituted the first demand for power beyond the strength 
of man, and hence began the need for transmission 
devices. The stones, which were no doubt at first 
relatively small, were in the beginning moved by 
hand much in the same manner as that now employed in 
the operation of small hand coffee mills. The employ- 
ment of animals and then of water power, both by the 
Greeks and Romans to turn the millstones came much 
later, perhaps 450 to 300 B.C. The Romans invented 
the vertical water wheel drive which was universally 
used for grinding flour until the close of the 18th cen- 
tury and is still very common in some parts of our 
own country as well as in the old world. 

Millstones are made of buhrstone, a form of silicate 
as hard as flint but not so brittle. They are usually 
from 4 to 6 feet in diameter and each consists of a 



Rubber in Industry 

number of pieces strongly cemented and bound together 
with iron hoops. The grinding surface of both stones 
is furrowed or grooved one being firmly fixed while the 
other is made to revolve. The motion is communicated 
through a vertical shaft secured to the revolving stone 
and the grain, previously cleaned, is fed by means of a 
hopper through the center of the upper unit. The 
flour passes out from between the stones around the 
circumference and is caught and directed by a suitable 
enclosure and spout. It is safe to assume that the 
rotative power for turning the larger mills was first 
developed by horses or human beings walking around in 
circular paths pushing or pulling the end of a lever 
mortised into the vertical mill shaft. The capacity of 
such a mill was, however, very limited for animals and 
men soon tired or became fatigued; but by harnessing 
the running stream with an undershot water wheel the 
old Greek and Roman miller obtained the dependable 
rotative effort needed. The power thus derived from 
the force of gravity caused the horizontal shaft of the 
water wheel to produce a strong turning effort at a 
speed dependent on the rate of flow of water and size 
of the wheel. Rut to transfer a maximum of power 
from the horizontal water wheel shaft to the vertical 
mill shaft constituted a perplexing problem. 

The first solution was the introduction of a right 
angle drive in which pins were driven through or into 
the adjacent ends of two shafts so that those protruding 
from the water wheel shaft engaged with others on the 
vertical mill shaft thus transferring power to the 
millstone. Later, it was discovered that two pulleys 
pressed into close contact were more reliable and less 
noisy than the peg system, but the slip between the 



Rubber in Industry 

two caused considerable annoyance which eventually 
led to the use of a drive with projections on the periphery 
of one pulley and sockets or recesses cut into the other — 
the forerunner of modern gears. 

The early pin and socket wheels of wood were not 
satisfactory but someone found that by covering 
the perimeters of friction pulleys with rawhide or cloth 
better results might be obtained. When the driving 
and driven shafts could not be contiguously located, 
trains of several such pulleys or wheels were interposed 
between them. Finally, however, a continuous band 
was made of the facing material and placed around the 
driving and the driven pulley eliminating the 
intermediate pulleys or wheels. Thus, we believe, was the 
transmission of power by belting inaugurated. 

The wind wheel was not seen until 600 A.D., nor the 
spinning wheel until the 15th century and the first 
historical reference to transmission of power by strings 
or bands appears in a description of the original spinning 
wheel; but from the time of the invention of the water 
wheel, an ideal means for the economical transmission 
of power has been sought. Friction pulleys, gears, rack 
and pinions, belts, electricity, water, air, oil, and many 
other mediums have been tried, but, any industrial 
plant today contains convincing evidence that belting — 
yes, rubber belting — predominates in the field of power 
transmission. Electric drives have not replaced it but 
have opened up vast fields of application which did not 
previously exist. 

Beyond the transmission of power rubber belting has 
found a new and extensive field — the transportation of 
materials. The invention of belt conveyors in their 
present form is comparatively recent, although in 1868, 



Rubber in Industry 

Mr. Lyster, an engineer of the Liverpool docks, found the 
old methods of conveying material inadequate for dock 
service; and began a series of experiments with endless 
traveling belts. His action opened up the field which 
has been so marvelously developed during the past 
twenty years. The economical status established by 
belting conveyors and the enormous volume in belting 
consumed by the trade may be taken as indicative of 
future possibilities in the belting industry. 

It is interesting to note that the first rubber belts 
were built along the same general lines as our present 
day production handicapped, of course, by lack of 
equipment and complete knowledge of compounds and 
ducks with which we, today, are prepared to serve the 
enormous demands made upon us. A history from 
early times on would, however, simply portray the 
battles with many rubber and fabric manufacturing 
obstacles which were finally to be overcome, taking us 
down to the entry of the Goodrich Company into the 
field about 1875; an account of trials which would no 
doubt be interesting, but which would not add materi- 
ally to the purpose of this work. Suffice it to relate 
that rubber belting, because of the finely graduated 
strength variations possible, and further, because indus- 
trial engineers have seen the desirability of having 
moisture- heat- and steam-proof belts, with maximum 
pulley adhesion and unsurpassed tensile strength, all 
obtainable at a moderate price, has proven more than 
popular and is in fact, growing in prominence with 
each passing day. We may, however, add to this, 
merely as a matter of information, the fact that rubber 
belting is a development of nearly a hundred years 
Thomas Hancock of London, England, having about 



Rubber in Industry 



1820 conceived the idea of using fabric impregnated 
and covered by rubber in the manufacture of trans- 
mission belts. 

Characteristics of Rubber Belting. Rubber belt- 
ing as we now must know consists of two or more 
plies of cotton duck held together by an elastic bond 
of compounded rubber and sometimes covered with a 
relatively thin sheet of the same material. Every con- 
ceivable combination of these three principal factors, i.e., 
duck, cover, and friction or ply bond, as the union is 
termed, has been tried out in practice and analyzed in 
our laboratories resulting in certain principles having 
been established as the best in manufacturing practice. 
The construction details such as duck weight and 
weave, methods of compounding, ingredients employed, 
and duration of cures are naturally held as the secrets 
of the various manufacturers; but duck must be em- 
ployed for strength and some form of bond or friction 
must be incorporated to hold the various plies together 
and, under certain conditions, a rubber cover must be 
applied. 

Being entirely a fabricated product, it is possible to 
construct rubber belting uniform in width, thickness 
and strength so that it will run true with no flapping 
or power losing traits which characterize many other 
types of belting construction. Rubber belting, properly 
made, has flexibility, which characteristic enables it to 
lie close to the pulley face and this combined with its 
natural adhesive properties, brings slippage losses down 
to a minimum and power transmission up to a maximum. 
Although these positive qualities indeed border on per- 
fection they are nevertheless, only developed through 



Rubber in Industry 

the most accurate and scientific construction methods. 
To illustrate this we may say that constituting the 
strength of the article into which it enters as a component 
part the first requirement of fabric or duck for belting 
is strength. Strength depends upon the material used, 
the length and quality of fiber, the size and twist of the 
thread or yarn and the design and processes of weaving. 

Cotton duck has been universally accepted as the 
standard belting fabric by all makers on account of the 
fact that it best combines the qualities required viz., 
strength of fiber and ability to withstand the heat of 
friction without marked deterioration. The more im- 
portant of the rubber belting factories have their fabrics 
woven according to their own specifications which de- 
termine such factors as the number of "picks" to the 
inch, number of strands composing each thread — warp 
and filler — and weight of the finished fabric per yard 
length of 42 inches wide, or in other words, 1512 square 
inches. 

Qualities and weights used are furnished in a wide 
range varying from light sheeting to 42 ounce duck 
and we may add to this the thought that there is little 
chance of determining the weight or characteristics of 
cotton duck after it has once been manufactured into 
belting. This material, however, differs considerably 
from that used in tires, hose, etc., in characteristics other 
than weight which is to say the ratio existing between 
the warp and filler threads is not the same; and further- 
more, when used it is not bias cut as is the fabric in 
many other rubber articles, but on the contrary laid 
with the warp threads running longitudinally with the 
length of the belt. "Warp" is the yarn running the 
direction of the fabric while "filler" is only another 
term for cross threads over which the warp is woven. 

7 



Rubber in Industry 

The Manufacture of Belting. *Since we have pre- 
viously been made acquainted with the characteristics 
of crude rubber and know in a general way the methods, 
if not the secrets of compounding, whereof the essential 
qualities of long life and stamina are obtained it is 
fitting that herein the description of the manufacture of 
belting should begin with the inspection of the fabric. 
But since we have also mentioned elsewhere that all fab- 
rics employed in the manufacture of rubber goods are first 
examined by experts to insure that the fiber, character 
of weave, weight, and tensile strength, are according to 
specification and capable of assuming the burden later 
to be imposed upon them we need not again dwell upon 
this feature. 

Following inspection, all fabric for belting is passed 
through a mechanical drier which drives out every par- 
ticle of moisture thereby leaving the material free from 
the deteriorating effects of water. The fabric in its 
original yardage is then fed between the two lower 
rolls of a friction calender where it is impregnated with 
the special rubber compound. "Frictioning" is the 
term applied by the trade to describe this impregnation 
of fabric with rubber, accomplished by the frictional 
action between two rolls running at differential speed. 
In this connection, we may mention further that belting 
fabric must not be woven so closely as to offer too strong 
a resistance to the penetration of the compound which 
is to say the covering of each thread with an almost 
frictionless coating of rubber must be accomplished. 
The term "friction" describes the elastic bond which 
holds the plies of fabric together, preserving the belting 
in its layer form, yet readily permitting a differential 
movement of the plies. The importance of this con- 

*See "A Wonder Book of Rubber." 

8 



Rubber in Industry 

struction may be better appreciated if the following ex- 
periment be carried out: Take a few cards from a 
pack, and bending them backward and forward, notice 
the movement of each in respect to the one below and 
above. The action of the plies in a belt when passing 
over a pulley is similar and for a proper distribution of 
the strains occasioned thereby some differential medium 
such as an elastic rubber adhesion is essential. This 
brings us to our main thought viz., that the construction 
of the duck has a strong bearing upon the value of the 
ply "adhesion" in that the surface and weave must 
afford suitable anchorage for the innumerable rubber 
tendrils or rivets. 

At this point let us halt in our description of pro- 
cesses long enough to mention that it is the aim of this 
company to so compound the rubber which is forced 
into and through the fabric that there will be an ad- 
hesion of long-lived quality though not necessarily of 
the highest initial strength. In other words, the value 
of a good friction lies in its elasticity and endurance or 
permanency rather than in the effort required to pull 
the plies of a new sample apart. If a strong "friction 
pull" were all that is desired a glued or dead union 
between the plies would show a far greater resistance 
to separation by ordinary testing methods than any 
other form of construction. A dead bond, however, has 
no life and when made to yield as the belt turns rapidly 
over the pulley the plies will not return to the same 
relationship but will break down causing permanent 
ply separation. The best belting practice, therefore, 
demands a tenacious, lively, friction with an enduring, 
nervy fiber, whose strength is exactly proportional to 
the strains met in actual service with a sufficient sur- 
plusage to meet unusual momentary overloads. 

9 



Rubber in Industry 

After passing through the calenders, all frictioned 
duck for belting is wound on shells with a liner fabric 
interposed which serves the double purpose of pre- 
serving the unvulcanized stock and keeping the various 
laps from sticking upon each other. 

To resume our description of the manufacturing 
processes, the desired width of belt is known and the 
necessary width of fabric to form the pairs of plies or 
double layers is determined; the calendered fabric then 
being cut on special machines according to a definite 
schedule. If the number of plies desired is odd a 
comparatively narrow single strip of this frictioned duck 
is used, flat, as the core ply; but if the number is even 
the first width is folded upon itself and pressed flat 
thereby making a double thickness core piece. Width 
after width is then folded over the first ply or core from 
both ways in such a manner that the edges do not 
meet at the center and the seams of the various plies 
do not register. Each ply as it is imposed is smoothed 
out the whole being subsequently unified through the 
application of pressure. 

Following the folding on of the last fabric ply a thin 
rubber cover may or may not be applied; or the belt at 
this point may be run through a series of sewing machines 
and receive several rows of stitching preceding the ap- 
plication of the rubber cover. After all building opera- 
tions have been completed the belt is sent to the press 
room where it is placed between the steam-heated 
platens or jaws of a huge hydraulic press, stretched and 
there subjected to a certain temperature under tre- 
mendous pressure for a length of time varying according 
to the nature of the ingredient used in the compound; 
or in other words, until completely vulcanized and abso- 
lute permanency of form thereby fixed. 

10 



Rubber in Industry 

To illustrate by example, let us suppose that we 
desire to make a 12 inch, 5-ply, friction surface belt. 
Since this belt is to be of an odd number of plies it 
necessarily follows that we start with a single strip of 
frictioned fabric cut by the slitting machine to a width 
a little narrower than 12 inches. Two other strips, one 
a little wider than the other, and both slightly more 
than 24 inches wide are cut from the previously fric- 
tioned duck and the three rolls placed on a shaft at the 
feed end of the belt bench. The narrower of the two 
wider strips is drawn along the bench to the point where 
the automatic folder is located. The narrow core strip 
is placed upon this wider piece and the latter folded 
over the core strip for a short distance near the end so 
as to effect an entry into the folding mechanism. The 
machinery is then started whereupon the core piece 
and strip forming the next two plies, pass through the 
folder and are rolled firmly between two cylinders. 
This is carried back over a conveyor to the feed end 
of the table and again rolled up. As the fabric lengths 
run out others are spliced on and the process con- 
tinues until the desired length of the belt is produced. 

This strip made up of the first three pJies is then pulled 
down the table to the point of beginning after a third 
strip is unrolled and placed upon the bench as was the 
second in the previous operation. The partly finished 
section of the belt then becomes the core piece upon 
which the third strip is folded forming the fourth and 
fifth plies. During this last operation the outside seam 
is reinforced with tape of a high quality gum, which is 
applied just before the belt enters the machine, where 
it is securely pressed into and over the opening between 
the edges, effecting a seal which excludes moisture and 
other foreign matter. 

11 



Rubber in Industry 

< 

As before mentioned, in the vulcanizing room are the 
long hydraulic presses, the platens or jaws of which are 
steam-heated. This un vulcanized belt along with four 
or five others is transported in a roll to one of the 
presses, placed on a revolving shaft and, section at a 
time, passed through the open jaws both ends of each 
section being clamped in adjustable hydraulic vices. 
The belt is thereby stretched, the hydraulic press is 
closed, and the cure effected while under this tension 
which insures the product being practically free from 
stretching later in service. 

The edges, however, although surrounded by high 
temperature have had no direct pressure applied while in 
the press and would therefore likely be under-cured and 
not resisting enough for the severities incident to extra- 
ordinary service which rubber belting meets. To 
properly fit them, we roll each belt and place it in a 
large cylindrical "pot heater" and there subject the 
edge only, to the proper heat until a partial |cure has been 
effected before the belt is run through the press. This 
insures a tough water-resisting edge. 

Except in extremely rare instances where special 
belts are desired the widths of which are greater than 
that of the machinery, our entire output can be said to 
be machine-made. Where unusually wide belts are de- 
manded for conveyor and special purposes they are 
built up by hand at tables, but according to the 
same general method as employed in the machine-made 
product. 

From a reading of this description concerning manu- 
facturing steps, our readers will have no doubt surmised 
that all rubber belting does not contain the same com- 
pounds and the same weights and qualities of fabric. 

12 



Rubber in Industry 

Such at least is the case and a moment's reflection on 
the multitudinous service demands placed upon rubber 
belting will clearly show why this is true. It will not 
be difficult, even for the novice, to realize that two 
plies of fine sheeting are more flexible than a single 
ply of heavier duck of the same strength and also that 
these two pieces will give the same or even greater 
strength than would a single ply of equal weight. By 
following this rule in construction we arrive at a light, 
extremely flexible, transmission belt, suitable for opera- 
tion over small pulleys running at high speeds. In- 
versely, we arrive at a suitable structure for heavy, 
slow-speed, main drive, transmission belts as well as the 
tough and strong construction required for elevator 
service and the many other service uses found in the 
industrial field. To further exemplify this statement, 
we need but mention that our brands and types in- 
clude constructions adaptable for all kinds of trans- 
mission service from the high-powered main drive to 
the light service auxiliary application. Also, our con- 
veyor belts are, in like manner, constructed to meet the 
many demands incident to the carrying of materials of 
all kinds from hot coke to breakfast foods; while heavy 
elevator belts also, are made to raise materials varying 
in weight from stone to dry bran. 

As a concluding thought to this discussion of manu- 
facturing processes let us mention that although we 
construct belts for nearly every known purpose, never- 
theless, the bulk of our output may be classified under 
these three general headings, viz., transmission, con- 
veyor, and elevator. The peculiarities incident to the 
construction of these types we will treat individually 
in the paragraphs to follow. 

13 



Rubber in Industry 

Transmission Belts. In any shop containing ma- 
chinery one easily distinguishes two kinds, driving 
machines, which may be water wheels, turbines, steam 
engines, gas engines, or electric motors, and driven 
machines, such as mills, rollers, lathes, planers, saws, 
looms and paper machines. There must always be 
some connecting link between a driving and a driven 
or work machine; that is, some means of power trans- 
mission. If the power and the work are not far apart 
shafting is used to extend the rotative energy to the 
vicinity of the work machines; but if they are far sepa- 
rated, sometimes miles or hundreds of miles, electricity 
generated at waterfalls or at the entrance of coal mines 
is conducted by wires to the vicinity of the work to be 
done and there caused to operate motors which become 
intermediate driving machines. 

The energy carried by a line of shafting or by a cur- 
rent of electricity must be applied locally to the work 
machines through friction wheels, gears, chains, electric 
motors, sheaves and ropes or pulleys and belting. Near- 
ly all machinery is fitted with belting in some form for 
connecting the driven machine with the source of power 
or for distributing the power to the various units of the 
machine itself; and its use is not by any means confined to 
any particular group of industries. To give an idea, how- 
ever, of how universally transmission belting is employed 
we need but mention some of the principal users, such 
as paper mills, textile mills, saw mills, printing plants, 
mining plants, etc. 

Every power transmission requirement is surrounded 
by conditions peculiar to the individual case and each of 
the mediums enumerated in the preceding paragraph 
has a particular adaptability; that is, there are some 

14 



Rubber in Industry 

drives which may be best served by silent chains and 
others by ropes or a multiplicity by belts. There are 
even some instances where it is expedient to connect the 
power machine and the work machine to the same 
shaft, but it is nearly always advisable to interpose 
between the driving and the driven units some flexible 
power transmitter which in case of accident will act as 
a shock absorber or safety link absorbing spasmodic 
shocks or rupturing when to hold would mean the 
destruction of valuable machinery. The requirements 
of some installations are not sufficiently well defined that 
the type of transmission may be readily determined, or 
that the wrong type is not occasionally chosen. The 
following general factors determine the merit of any 
transmission medium adaptable to the space and other 
peculiar requirements of an installation. 

1. Uniform construction and fine strength graduation. 

2. Flexibility and elasticity. 

3. Ability to withstand climatic conditions and heat 
variations without undue deterioration. 

4. Reliability in operation. 

5. Economy of maintenance. 

6. Low power consumption. 

7. Reasonable first cost. 

8. Expense in the long run. 

Take directly connected motors, gears, chains, ropes, 
leather belts, steel belts, hair belts, and Rubber Belts, 
one by one and examine them for the possession of all 
or lack of any of the above qualities and it will become 
obvious that Rubber Belting deserves the position it 
now occupies in the field of power transmission — the 
most universally and extensively used of all mediums 
for the transmission of power. It, therefore, may be 

15 



Rubber in Industry 

i 

asserted that the discovery of the process of rubber 
vulcanization during 1837-39 has strongly influenced the 
present status of power transmission. 

The first patents granted for the manufacture of 
leather belts bear the same date; but there was little 
demand for transmission appliances of any sort until 
after the Civil War when the growth of manufacturing 
industries through the extension of railroads received 
a powerful stimulus. Leather was then more easily pro- 
cured and prepared, which factors, together with the 
circumstance of its wide distribution over the earth 
caused this material to immediately gain prominence in 
this field. As industries developed, however, the steadily 
increasing demand for leather from many other indus- 
tries caused advances in the price which have greatly 
limited the use of this type of belting. 

Leather is a good belt material for general trans- 
mission service but the strength variations have always 
been so coarse that it has never been possible to exactly 
proportion the weight of the belt to the work to be 
done. In other words, the standard practice in leather 
belt construction provides only for single, double, and 
triple thicknesses; the double leather belt being one and 
six-tenths as strong as the single while the triple thick- 
ness affords only twice the strength of the single con- 
struction. By coarse strength graduation we mean 
therefore, that if a single leather belt of a certain width 
is capable of transmitting 60 H.P., a double leather 
belt of the same width will transmit only 96 H.P. and 
it would be necessary to employ the double belt for 
75 H.P. when the strength afforded would not be re- 
quired. On the other hand, fine graduations may be 
obtained in the rubber belt which as will be later 

16 



Rubber in Industry 

described, is made up of several plies of fabric which, 
working together, constitute the strength of any given 
belt. The omission or addition of one ply varies the 
strength slightly but sufficiently to almost exactly afford 
the proper proportion. 

However, on account of its great endurance and many 
good qualities and despite its cost, sufficient leather 
belting is still in service to make it the second most 
important material used for belting. 

Plain stitched duck, painted duck, balata impregnated 
duck, hair, steel, and several other kinds of material 
are used for making belts; but only one other, viz., 
canvas, is sufficiently important to warrant any special 
discussion. Periodically, canvas belts rise above the 
horizon of obscurity by virtue of their relative cheapness 
and are sustained for a time by extravagant guarantees; 
but the truth soon penetrates the fog of deception and 
the experimenters almost invariably return to the stand- 
ard — Rubber Belting. In other words, the day of 
argument for and against the use of rubber belting has 
passed. Its advantages are now quite universally 
recognized. 

As we have made mention in the historical introduc- 
tion to this chapter, the transmission of power was the 
original service performed by belts. To this we may 
now add the thought that although time has added 
many other uses, nevertheless, the transference of 
power from one pulley to another constitutes the greatest 
and most diversified problem of belting manufacture. 
Like the history of belting in general the story of 
Goodrich rubber belts is built around a transmission 
belt as a foundation. Today Goodrich belts are built 
according to specifications which practical service ex- 

17 



Rubber in Industry 

perience has taught us; combining the fine balance 
necessary to meet the various requirements most satis- 
factorily. Old types and constructions have not sur- 
vived but constant development and improvements 
have established new constructions and brands. Not 
unique necessarily but of real sales value in themselves 
these advancements have tended to strengthen and 
standardize our line and to support the Goodrich repu- 
tation for quality. There is no "best" Goodrich belt; 
but each grade has been developed to serve definite 
requirements most economically. Difference in price, of 
course, indicates a variation in quality but for this 
there is a reason. In other words, we would not recom- 
mend our "Commander" for an installation where re- 
quirements could be fully met by a cheaper grade. It 
would not be economical nor any more practical than it 
would be to deliver groceries from house to house with 
a five-ton truck, and a like comparison somewhat 
modified, may be made between any other two grades 
of our line. 

Our line-up of regular grades covers the entire field of 
belting requirements in well graduated steps the differ- 
ence between one class and the next higher or lower 
being represented in the variations of quality and weight 
of the component parts. No particular advantage to 
the readers will accrue from a detailed discussion of each 
brand, yet it will be appreciated that each represents a 
special development and is in some detail different 
from all others. The elimination of superfluous grades 
has made this difference in our line more marked than 
in the lines of other belting manufacturers. To be 
more specific, in our heavy duty types, the friction 
aside from containing great adhesive strength is long- 

18 



Rubber in Industry 

lived and elastic enough to stand up under the high 
speed and sudden strains caused by fluctuations in the 
power demanded from time to time. On the other 
hand those for lighter service, such as auxiliary drives, 
although substantially made from thoroughly reliable 
materials require in place of an extreme quality only 
a medium grade of friction to bind together the medium 
grade plies of fabric. 

Rubber belting as first manufactured in all grades 
was finished off with a rubber cover. Today, however, 
friction surface, i.e., without a cover, the rubberized 
fabric alone being used, is rapidly increasing in popu- 
larity. Due largely to research of paper mill belting 
needs we early found this type superior to the rubber- 
covered for the particular requirements of paper making 
machinery, which involves many drives of the severest 
nature. In other words the high quality of stock 
necessary in a rubber-covered belt to secure the extra 
flexibility required in paper mill service is so great that 
the price of such a belt would be almost prohibitive, 
whereas, in the friction surface type the extra 
cost may be placed in a high quality duck, im- 
pregnated with the best possible friction. And the 
satisfaction which this coverless rubber belt gave in 
paper mills has caused manufacturers in general to 
gradually introduce it for their hardest drives with the 
result that today most Transmission Belting for extreme 
services is of the friction surface type. This insures 
against the rubber heating, hardening, and peeling off 
the belt which of course is the determining factor in 
the efficiency of a belt. "A belt can transmit only as 
much power as it takes from the periphery of the driving 

19 



Rubber in Industry 

pulley and this quantity varies directly with the nature 
of the surfaces in contact." 

A new departure in the belt field which Goodrich 
introduced a few years ago, and which is today proving 
to be an added asset to hard drive efficiency is a "gum 
cushion" placed under the top ply of the fabric. This 
layer of rubber compound affords special resistance to 
moisture where the outer ply is subjected to consider- 
able wear and through it the belt attains an unusual 
degree of flexibility, a feature of special importance to 
drives having small pulleys, quarter turns, or snubbing 
idler attachments. Furthermore, this gum cushion 
materially lessens the strain imposed on the inner plies 
of duck; but the best proof of the logic of this feature 
lies in the popularity it is gaining and the number of 
repeat orders we are constantly receiving for belts of 
the "gum cushion" type. 

As a proper concluding remark to this brief description 
of transmission belting let us mention that our experi- 
ence, research, and study of rubber belting manufacture 
has brought us to a place where we can literally prescribe 
the proper type for any power transmission problem 
with a high degree of accuracy. In other words, we 
have a line-up of constructions which includes belts that 
will positively take care of any drive where a rubber 
belt can possibly be used; and at a reasonable cost. 

Conveyor Belts. As mentioned in the historical in- 
troduction to this chapter the idea of the application 
of belting to the problems of the transportation of 
materials is accredited to Lyster of England, who in 
1868, employed flat bands or belts in the handling of 
freight on the docks at Liverpool. The belt conveyor, 

20 



Rubber in Industry 

however, did not come into general use until about the 
year 1894, at which time Robins invented the type of 
materials conveyor which is in such general use today. 
Although worn transmission belts had long been used 
around sawmills in what today are popularly termed as 
"drag conveyors" for carrying sawdust and other refuse 
to the fuel bins whence it was fed into the furnaces it 
is indeed to Robins that the introduction of belting as 
a materials transportation factor may be properly 
assigned. Some will recall this drag conveyor which 
consisted of a wooden box or trough, a "foot" and 
"head" pulley and the belt upon which there was 
usually fastened at intervals of a foot or two, wooden 
cleats. This makeshift, for such it was, as may be 
imagined could not be operated without considerable 
friction and therefore only the lightest of materials such 
as sawdust could be carried and even under these con- 
ditions the belting soon wore out. It has only been 
since the introduction of the almost frictionless trough 
carrier idler system, invented by Robins that the con- 
veyor belt has come into such general use that hardly 
a single large industrial plant where materials are 
handled in bulk is without one or more belt conveyors. 
In its simplest form a belt conveyor consists of two 
large pulleys, one at either end, over which the desired 
length of belt is stretched under sufficient tension to 
provide the traction necessary on the driving pulley. 
One of these pulleys, usually the one at the discharge 
end, is connected to an electric motor or a line shaft 
through suitable gear or belt and pulley speed reduction. 
Under the upper run of the belt, carrier idlers are 
mounted every 4 or 5 feet to support the loaded belt; 
and under the lower run, return idlers are mounted 

21 



Rubber in Industry 

every 10 or 20 feet to support the slack side of the 
belt. The carrier apparatus is one of the most impor- 
tant factors and consists of units of three or more small 
pulleys or rollers mounted upon stands so as to give the 
belt the necessary curve or trough. These small idler 
pulleys which are usually 4 or 5 inches in diameter and 
4 to 6 inches long may be mounted upon plain bearings 
or ball or roller bearings and the shaft of the carrier 
idler set upon which the rolls are mounted is usually 
hollow, so that lubricant may be readily applied to the 
bearing surfaces. 

There is no method for continuously handling large 
quantities of loose materials horizontally or up moderate 
inclines that is anywhere near as satisfactory and econom- 
ical. In fact, no other method is sufficiently prom- 
inent to be classed with belt conveyors and the reasons 
that lead up to the selection of this method of trans- 
portation in one instance may differ widely from those 
that influence the same choice of another. The space 
available for the installation is sometimes limited, 
which is a factor since belt conveyors have a capacity 
in proportion to the amount of space they occupy. 
Power requirements are, however, always low in com- 
parison with other methods of handling; the apparatus 
is light in weight, economical in operation and main- 
tenance and practically free from shutdown when com- 
pared with other handling systems. Moreover there are 
very few instances where belt conveyors cannot be used 
with better results than any other method for carrying 
materials over short distances. It is estimated that 
the low average cost of conveying loose materials by the 
man and wheelbarrow method is 15 cents per ton.* A 
belt conveyor will handle hundreds of tons per hour 

♦1015 Costs. 

22 



Rubber in Industry 

at a cost averaging much less than one cent per ton 
and it is not an unusual circumstance to learn of an 
installation where the belt has been put on and run for 
several years with scarcely any evidence of trouble 
entering into its operation. 

Conveyor belts are somewhat similar in construction 
to those used for the transmission of power the principal 
difference being that the former are nowadays always 
provided with a rubber cover owing to the fact that the 
service they perform involves considerable surface wear. 
It will be recalled that the first transmission belts were 
built with rubber covers and that these were used at 
first in conveyor belt service. The use of other con- 
structions soon developed the fact that the rubber belt 
with the rubber cover resisted abrasive wear much 
longer than those of canvas or friction surface con- 
struction. The importance, therefore, of the rubber 
cover we may say was almost accidentally discovered. 
As new uses developed it was found that transmission 
belt construction did not adapt itself particularly well 
to conveyor service. This statement we may exemplify 
by saying that the proportion existing between the 
width and number of fabric plies is different in conveyor 
belt practice. In other words, fewer plies are required 
and they are made lighter than in transmission belts 
since quite as great tensile strength is not necessary; 
whereas extreme flexibility is an essential. Conveyor 
Belt duck, therefore, although it must provide for 
longitudinal strength must primarily permit a greater 
flexibility cross-wise than the ordinary ducks used in 
drive belts. This feature is essential because the belt, 
although made of 6 or 8 plies of duck, must in many 

23 



Rubber in Industry 

installations "trough" in order to carry the materials 
without excessive spillage. 

The friction between the plies of Goodrich-made 
Conveyor Belts is a high quality, substantial rubber 
compound, having strong elastic tendrils with dis- 
integration-defying properties which will hold the plies 
together during more than the normal useful life of 
such a belt. The thickness of the cover and number 
of plies are proportionate to the weight of the material 
carried and force of the blows to be sustained at the point 
of loading rather than to tensile strains which are almost 
negligible in conveyor service. The cover in our regular 
grades varies in thickness from ■£% to 34 inch, being 
made of compound which has been developed especially 
to resist abrasive wear and mild chemical reaction. And 
almost any conditions in special service brands may be 
provided against. The cover of a Conveyor Belt is real- 
ly where the greatest need for scientific compounding is 
manifest, for due to the abrasiveness of many materials 
handled and the injurious effects of blows occasioned by 
the delivery of heavy, sharp material to the belt's sur- 
face, protection of the fabric body from moisture is dif- 
ficult. It is, however, a fact that continuous testing 
and experimentation have enabled us to increase the re- 
sistance to abrasion in our cover stock ; at the same time 
decreasing the cost per square foot which circumstance 
further exemplifies the truth of our contention that in 
many uses rubber should be highly compounded to 
achieve the highest efficiency; notwithstanding 
that many engineers believe belt quality is pro- 
portional to the pure gum content of the com- 
pound used. 

Frequently, conveyor belts are installed in wooden 

24 



Rubber in Industry 

troughing which form of installation unless carefully 
made is severe on the belt's edges. Occasionally, on 
standard idler carrier systems the belt will run out of 
line causing the edges to be rubbed against the gu ie 
idlers. In either instance unless construction provides 
against the abuse to the belt along its edge from these 
causes, the cover will be broken away along the edge 
and the whole belt thereby prematurely destroyed. 
Molded rubber edge strips have been used as a pre- 
ventive to disintegration through unusual abrasion, but 
this form of construction has not always worked out 
to entire satisfaction. We employ a special edge con- 
struction whereby the top cover in one piece is carried 
around both edges to form a union with the back cover 
of the belt a short distance away from the edge. Thereby 
we eliminate the possibility of the gum tearing loose and 
thus an effective edge protection is assured. Further than 
this, a special method of cure peculiar to the construc- 
tion of Goodrich conveyor belts constitutes a measure 
which increases the adhesion of the cover stock along 
the edges. 

The transportation of ordinary materials demands no 
features in belt construction other than sufficient 
strength, flexibility, endurance, and reasonable cost; 
but materials handled in many industries are, un- 
fortunately, of such a nature that special developments 
are necessary. For example, the presence of strong 
acids or extreme heat requires a grade of cover and 
sometimes a body construction which would not be 
economical in general practice. Then again, some 
materials handled are in such form that they would 
spill from a flat belt and consequently flanged edges 
are required ; as in vanner belts. For service where con- 

25 



Rubber in Industry 

ditions are too severe for our regular grades and for 
special machine requirements we accordingly furnish 
special designs. A few of these special constructions for 
unusual service are: Our best quality general service 
belt made up in 42 oz. duck for extra heavy duty. 
Dredge Stacker Belt, an extreme quality duck friction 
and cover combined in a belt designed for use in con- 
veying the tailings or refuse rock away from gold mining 
dredges. Gossette Belt, regular in its construction but 
with a cover, back, and edges especially compounded to 
resist the chemical reaction of pulp as it is handled 
in the beet sugar plants. Canning Belt, a regular con- 
struction for the handling of fruits, vegetables and 
meats in canning factories but made with a cover of 
appropriate thickness, quality, and color. Vanner Belts, 
so named, used on machines termed vanners in the 
mining industry for the separation of copper, gold, and 
other minerals from the ore bearing sludge or crushed 
rock, are a special construction throughout, in endless 
form usually 72 inches wide with flanges at either side 
designed to keep the sludge which is mixed with water, 
from running off onto the floor. Although there are 
also many other service requirements demanding special 
construction, those named will suffice to establish in 
the minds of our readers the extent to which we go, in 
adapting our products to all industrial requirements. 

Early in the history of belt conveyor development, 
there was invented and patented a special construction 
known as the "step-ply-belt." This consists of a cer- 
tain number of plies of duck running clear across the 
belt with two or three additional thicknesses or plies of 
duck at each edge of the belt. Over these a rubber 
cover is applied so that the top surface is flat or level 

26 



Rubber in Industry 
> 

thus giving a greater thickness of rubber cover at the 
center of the belt where there are fewer plies. The belt 
may consist of four plies at the center and two additional 
plies at the edges. When the thickness of cover at the 
center is &" as in this case, the cover at the top near 
the edges would be only y%' or perhaps even less in 
thickness. The theory underlying this construction 
was that greater thickness of cover could be thus 
secured toward the center of the belt where the wear 
on the surface is greatest and at the same time greater 
flexibility secured for troughing by the stepped arrange- 
ment of the plies. 

Now while this idea may theoretically be good, it 
has not worked out in practice successfully. The 
actual wear and tear on the surface of the belt is great- 
est, not at the center of the belt, but along the edges 
of the load this being not very far from the edge of 
the belt at each side. This causes the stepped ply 
belt to wear out more quickly where the cover is thin- 
nest and where it should be particularly thick to resist 
this wear. Secondly, there are weak lines along each 
side of the belt where the ply thickness and cover 
thickness changes. This tends to cause the belt to 
crack and the plies to separate along these weak lines 
especially so when the shape of the troughing pulleys 
is not just what it should be. If we have, for instance, 
a belt 36" wide these weak lines may come, say 8" 
from each side. Then suppose we have a 5 roll trough- 
ing idler over which this belt is to run. If the spaces 
between the outer pair of rolls happened to be a little 
wide and happened to coincide with the weak lines 
of the belt, the belt will squeeze into these spaces and 
break down very quickly along its weak lines. 

27 



Rubber in Industry 

This has actually been found to have happened in a 
great many installations where stepped ply belt was 
originally installed. The result has been that in very 
few instances where the original conveyor belts have 
been worn out they have been replaced by the same 
type. 

As has been noted before, belt conveyors are em- 
ployed in thousands of industries and utilized for 
handling every conceivable kind of material. The 
more ordinary uses are fairly well known but many 
will be surprised to learn that belt conveyors are em- 
ployed in the handling of pills, pins, rubber bands, 
raw cotton, mail, waste paper, magazines, canned 
soups and vegetables, phonograph records, wet con- 
crete, ashes, shoes, hats, automobile parts, and a mis- 
cellany of bundles and packages in large retail stores. 
This method of handling products is, however, more 
extensively employed in the transportation of bulk 
materials in the following industries than in others, viz., 
mines, sand and gravel pits, cement plants, paper mills, 
and bottling works. In its numerous applications the 
belt conveyor may serve to carry thousands of envelopes 
away from the machine every hour, or it may hourly 
supply the stamp mills in a reduction plant with hun- 
dreds of tons or more of heavy ore. This statement 
brings us to our main point, namely, that the capacity 
of belt conveyors is almost unlimited, depending of 
course upon the width, the speed at which they are 
run and the weight of the materials transported. The 
selection of the proper size belt is, however, not a mat- 
ter of conjecture but on the other hand formulas 
derived from mechanical calculations and experiences 
embracing the various factors of a particular applica- 

28 



Rubber in Industry 

tion may be used to accurately determine width, num- 
ber of plies and speed necessary to serve a given set 
of conditions. For example, the width of a conveyor 
belt is determined by the following formula. 
62,000 G 
W= 



Sg 



when, 



C=Capacity in tons per hour, 
S=Speed in feet per minute, 
g= Weight in pounds of one cubic foot of the 
material to be handled. 
To illustrate this formula let us determine the width 
of a conveyor, operating at a speed of 300 feet per min., 
to handle 50 tons of coal per hour. Goal weighs 50 lb. 
per cubic foot. 

G=150. S=300. g=50 and thus 
62000x150 

W= or 25" is the width of belt required. 

300x50 
Using this formula as a basis, by transposition of the 
equation we may determine the width or speed when 
the capacity and one of these factors have been pre- 
determined: 

W 2 Sg 62,000 G 

G= S= 

62,000 W 2 g 

As before stated, very little power is required to keep 
the belt in motion because the load at any given time 
is relatively small the volume or capacity being main- 
tained by the speed at which the belt travels which 
varies from 200 ft. to 600 ft. per minute according to 
the rolling tendency of the material. The belt is the 

29 



Rubber in Industry 

most important factor, but if the idlers are not kept 
properly lubricated and the head and tail pulleys are 
not maintained in nearly perfect alignment it may not 
give satisfaction. Conveyors are frequently located in 
exposed places and it is not unusual to find a belt drag- 
ging over dead or frozen rollers which cut the cover and 
fabric to pieces quickly. Conveyor belts are not quickly 
worn out by carrying materials but rather by loading; 
and for this reason, every effort is made to have the 
bins and chutes so designed and constructed that the 
delivery of material to the belt will be in the direction 
in which the belt is moving and at as nearly the same 
speed as possible. 

There are, however, several common abuses to which 
conveyor belts are frequently subjected which when 
avoided by careful and intelligent handling of the equip- 
ment result in a considerably extended length of belt- 
ing service. Some of the most glaring of these are over- 
speeding, which increases abrasive wear; misaligned pul- 
leys and idlers which increase edge wear; too much 
tension which will stretch the belt, pull out the lacings 
and may ruin the machine under sudden heavy loads; 
long lay-ups of exposed equipment where the belt is 
not removed, causes it to deteriorate prematurely by 
the action of rain, sun, and frost; and lastly, by im- 
properly installed skirt boards, under which coarse par- 
ticles of the material may become lodged and by dragging 
along, cut and injure the rubber cover. 

Skirt boards are frequently necessary where light or 
fine materials are handled, such as sand to keep them 
from spilling over the edge of the belt. These should 
be flared rather than installed horizontally and then 
cut away underneath at a slight angle, starting from the 
back. 

30 



Rubber in Industry 

Usually, belt conveyors are installed in a horizontal 
position but they may also be slightly inclined. The 
angle of inclination, however, is limited to that at which 
the material starts to roll scarcely ever exceeding 20 to 
23 degrees from the horizontal. 

The question of power transmission enters into con- 
veyor belt practice but does not determine the number 
of plies or weight of the belt as is true in transmission 
belt construction. Other factors such as belt body 
sufficient to support the weight of materials carried 
without excessive sagging between the idler sets de- 
mand a belt of such proportions that much greater 
strength is provided than is necessary for the trans- 
mission of the very small amount of power required to 
keep the load in motion. On account of the low speed 
and extreme length of belt, power transmission in con- 
veyors is, therefore, not efficient. 

Belt Elevators. When the angle of elevation to 
which material is to be transported is abrupt or the 
space limited so that the belt will have to be run at a 
steep angle, or vertically, buckets are fastened to it and 
it becomes an elevator instead of a conveyor. On 
account of the low first cost, economy of operation and 
dependability, belt elevators are well adapted to the 
lifting of all kinds of grain, ore and other materials ex- 
cept in cases where the material to be moved is not 
loose but must be scraped or dug up as is the case where 
excavation is made by trench digging machinery. Here, 
double chain elevators seem to be better adapted on 
account of the heavy nature of the work. Belt ele- 
vators are used extensively in many industries but 
especially in the mining industry where they, with the 

31 



Rubber in Industry 

conveyors, are the arteries of the mills. They are the 
source of a great deal of trouble and no effort is spared 
by the careful mill owner to make his elevators as nearly 
ideal as possible as far as the equipment is concerned. 
The belts are subjected to all manner of abuses and if 
one fails unexpectedly, the ore circulation of the entire 
plant becomes clogged causing a complete shut-down. 
One sudden shut-down through belt failure, will very 
likely cost in lost output, extra labor, superintendence 
and repair expense, more than the cost of several good 
belts or even an entire elevator equipment. 

The difference between elevator and conveyor belt 
requirements should be evident. But to make certain 
that our reasons are understood thoroughly by even 
those who have not heretofore come in contact with 
elevator belt practice we will mention that this service 
is by far the most severe to which belts are ordinarily 
subjected. Therefore, to provide against the losses of 
delays incident to frequent breakdowns, elevator belts 
are built stronger and heavier than those used in con- 
veyor service. Elevator belts are also made up of a 
greater number of plies so that they will withstand the 
breaking effort of bits of stone, etc., which are bound to 
get caught underneath and pass around the pulley; and 
as an added reason, to afford sufficient anchorage for 
the bolts or rivets which hold the buckets in place. The 
backbone of an elevator belt is, in fact, its fabric structure 
and sufficient strength must be built into the body in 
order to offset the weakening due to the bolt hole 
punchings and the resultant action of moisture. 

Elevator belts sometimes run through water and 
frequently handle wet materials continuously. Natur- 

32 




Where Goodrich Belts are Vulcanised 



#? " A Gold Dredge 




As Rubber Belting Predominates in the 
field of Power Trans mission 




Conveyor Belts afford the most practical means of handling 
materials over short distances up to about 1000 feet 



An Incline Coueyov 





The driving and 
Driven. Machines 




TYPES - 1 Rubber Covered ■ — ^Friction Surface — ■ 
5 Stitched_ apd Rubber Covered — ^High Speed, 



Small Pulley — -Gum Cu?hio, 



Rubber in Industry 

ally the severities of such service must be provided for 
in the quality of friction as well as in quality of fabric. 
In other words, the presence of fabric quality alone 
will not do the trick; but in order that ply separation 
may be prevented and as a consequence, the belt other- 
wise good be made useless, a high quality of friction 
rubber must be present. Only by such a balanced con- 
struction can the belt manufacturer hope to deliver a 
dollar in service for the dollar spent. 

Balata belts, woven belts, and impregnated canvas 
belts of many types, have been experimented with in 
various fields but in the main have proven to be dismal 
failures for the more severe belt elevator service. In 
other words the rubber belt is the only type which has 
ever demonstrated its economical value in actual serv- 
ice, giving uniform satisfaction. Mill-men generally 
stick pretty closely to the high class rubber belting for 
elevator work for experience has shown that the better 
the belt the cheaper it is in the end. There is no 
question but what with a good belt the number of in- 
terruptions is materially reduced. 

Rubber covered elevator belts are coming more and 
more into general use. On the pulley side, the smooth 
surface thus gained increases the co-efficient of friction 
and prevents belt wear from the particles of material 
which get between the driving surface and the foot or 
'"boot" pulley. The degree of wear in this instance is, 
however, somewhat dependent upon whether the ma- 
terial is dropped into the boot and scooped out by the 
buckets or poured into the buckets directly. A rubber 
cover on the bucket side also prevents abrasive wearing 
of the belt from particles of material which are nearly 
always bound to get between buckets and belts, thus 

33 



Rubber in Industry 

subjecting the surface to a grinding action from the 
moving of the buckets as they pass over the pulleys. 
In some instances these rubber covers have, according 
to mill men, not proven practical but we are, however, 
of the opinion that this is because the right specifications 
were not worked out for the particular service require- 
ments. It has been claimed by some that the rubber 
on the back of the belt is of doubtful value because a 
few weeks hard service peels it off exposing the canvas. 
To us this statement seems an impeachment of the 
adhesion between the particular rubber cover used and 
the duck rather than an argument against the use of 
the rubber cover. Why should not conveyor philosophy 
apply in elevator belt practice? 

Goodrich Elevator Belting, the same as our conveyor 
types embodies the latest developments in the manu- 
facture of rubber belting for this particular service. 
Our engineers have made a careful study of the con- 
ditions surrounding the operation of belt elevators in 
various industries and our constructions have accord- 
ingly been especially adapted to the service as it exists. 
In selecting the fabric we have considered the strength 
necessary to guard against the pulling through of the 
bolts and we have furthermore developed a weave which 
affords the necessary body at the same time permitting 
the rubber compound to permeate each strand and sur- 
round the threads with a frictionless covering of rubber. 
The Goodrich organization has probably analysed the 
performance of more mining belts in actual field service 
than any other manufacturer. The result is common 
sense practical construction along with properly balanced 
rubber and fabric of the correct quality for each particu- 

34 



Rubber in Industry 



lar service. This common sense construction has developed 
a product embodying the following advantages: 
In general Maximum flexibility. 

Sufficient strength for every require- 
ment. 
Very little stretch. 
Great endurance. 
Will not break before it is worn. 
In fabric Toughness and durability. 

A secure anchorage for bolts and rivets. 
A body that bolt holes will not weaken. 
In friction Insurance against ply separation. 
Exceptionally long life. 
The best protection against moisture. 
Gives the belt extreme pliability. 
In cover Protection to the fabric and friction. 
Toughness and resiliency. 
Wear resistance. 
In service Belts which are rendering excellent ac- 
counts of themselves. 
Almost every day we learn of new uses for belt con- 
veyors and belt elevators. Furthermore, their advan- 
tages over other methods of short distance transporta- 
tion are so pronounced that it is reasonable to anticipate 
a broad expansion in this field already extremely at- 
tractive to the belting manufacturer. The B. F. Good- 
rich Company claims the distinction of having built the 
first conveyor belt for the inventor and patentee of 
this useful device — the conveyor; and, through develop- 
ments based on experience with conveyor and elevator 
operation all over the country we have up to the present 
been able to maintain the leadership in the production 

35 



Rubber in Industry 



of a high quality belting for these uses. We do not, 
however, manufacture idler rolls or other accessory 
machinery. 

Brands. In accordance with our established policy 
each brand in our belting line whether transmission, 
conveyor, or elevator construction, stands for a particular, 
and in many instances a special development designed 
to meet certain conditions. Each of our brand names 
is well known to the trade and new and catchy trade- 
marks are never employed to mislead the trade or 
deceive the consumer. In a work such as this, however, 
a full description of brands and their peculiarities in ap- 
plication would be of little practical value and for this 
reason there is little else beyond the thought just ex- 
pressed which would add to the value of this discussion. 
We may mention, however, that the standardization of 
our line is a constant source of pride to our sales organ- 
ization. 

Even from the very brief descriptions which we have 
been able to allot to the three sub-divisions under this 
general topic of belting the reader has no doubt seen 
that success in this field depends primarily upon build- 
ing belts which will satisfy particular service demands, 
and, having built them in seeing to it that the right 
quality and brand is sold for each installation. At 
least this is the thought which we have intended to 
develop and with this in mind we have from the be- 
ginning not only constructed our product but have 
trained our men to make common sense recommenda- 
tions in selling. When one considers, however, that 
nearly every shop or factory of any description is 
literally laced down with a maze of belting, only then 

36 



Rubber in Industry 

can conditions encountered in service commence to be 
realized. Not only are lathes, planers, shapers, looms, 
and thousands of other machines driven by belts but 
as we have mentioned, materials are carried from floor 
to floor or from building to building by belts either with 
or without the aid of buckets. 

There is yet another thought in this connection which 
when extended by further reflection may serve to ex- 
plain to those who have just arrived, the fundamental 
reasons back of our manufacturing and selling policy. 
This is the fact that we construct to exceed require- 
ments not merely to meet them, which explains clearly 
the reason for the reputation we have gained in this 
belting field. Our customers are assured of the very 
best product that close study of conditions, expert se- 
lection of raw materials and modern manufacturing 
equipment can produce. When the Goodrich or Dia- 
mond trademark or brand appears upon a belt they 
know that it is a guarantee of protection and that our 
reputation for high grade goods and square dealing in 
this field has been maintained over a period of a half 
century, that every brand which is stamped as our 
product is done so with the realization that we must 
live up to that reputation. Every item in our belting 
line stands as a representative of the highest standard of 
service value in its respective class and we in all instances 
stand back of the brand. 

Aside from our numerous standard constructions as 
furnished for these three service requirements, i.e., trans- 
mission, conveyor, and elevator, we manufacture special 
belting for oil well drilling, polishing machinery, car 
axle lighting systems, animal dehairing machines, etc. 
But inasmuch as these are special constructions, de- 

37 



Rubber in Industry 

signed for peculiar service requirements, although con- 
structed and employed similarly to standard belts, we 
do not believe it advisable to describe them individually 
in this work. 

For convenience in handling, shipping, and selling, 
all belting, of whatever nature, is packed in rolls. 




38 



CHAPTER TWO 

Rubber Hose 

T~\EFINITION. The word hose as used throughout 
*-J this work designates a flexible pipe for conveying 
fluids, air and other gases as well as dry sand, powdered 
materials and sometimes wet earth. To be universally 
acceptable this type of conveying medium must not 
only be capable of bending without breaking or col- 
lapsing, but must also possess endurance and the quality 
of lightness that it may be easily handled yet perform 
severe service. In addition, the construction of hose 
must be simple in order that it may be sold at a reason- 
able price. Iron, steel, copper, brass and lead piping 
are flexible to a limited degree, especially the latter; in 
fact, this material is frequently employed where the 
positions of two connections are not fixed nor constant. 
But pipes made of metal do not long endure constant 
bending and will not permit cold bends or short radii 
without permanent setting, collapsing or breaking. 

In the all-inclusive sense of the word, herefore, hose 
may be made of almost any material; but fabric and 
rubber in various combinations are by far the most 
extensively used. In fact, with the exception of a 
metallic conduit made of helically wound interlocking 
strips of metal with asbestos or some other fibrous 
material interposed between the spirals to effect a seal, 
a small amount of linen and cotton fire hose, Rubber 
Hose may be considered the universal standard flexible 
medium for conducting fluids and gases. The metallic 

39 



Rubber in Industry 

helix variety is used to a limited extent for short steam 
connections; but this type is, however, extremely ex- 
pensive and its use therefore, confined to a small field 
of application. Woven hose of cotton or linen has had 
a wide distribution especially for fire-fighting purposes, 
but is not acceptable in the greater majority of uses 
where a flexible conducting medium may be employed 
to advantage. Rubber hose, so termed, i.e. that con- 
structed from compounded rubber and rubberized fabric 
either in the form of a wrapped or braided carcass can 
therefore, be said for our purpose to define the word 
Hose. 

Historical. Throughout the early history of me- 
chanics, frequent references are made to flexible pipes 
made of rawhide or leather for the purpose of conduct- 
ing liquids. Leather in fact occupied a very important 
position in the list of hose materials even as late as 
1859. Beginning, however, with this date, its use com- 
menced to decline until today this material is no longer 
thought of in this connection. There seemed to be no 
general type of construction, but the most common 
variety was produced by the expedient of building 
strips of leather over a mandrel or form and then sew- 
ing the edges together. As may be imagined, however, 
leather hose never proved satisfactory from a practical 
standpoint and was at best found to be only a make- 
shift. 

Even as early as 1827, Hancock and Macintosh had 
introduced into Europe a hose made of India rubber 
and fabric. Hancock's Personal Narrative, The Manu- 
facture of India Rubber, describes the early processes 
employed by them in such an interesting way that we 

40 



Rubber in Industry 

feel justified in incorporating at this point a brief para- 
graph or two from his description. 

"We manufacture hose-pipes and tubing of caoutchouc, 
gutta percha, and compound in various ways. We take 
threads made of either of the above, of a size propor- 
tioned to the hose, and braid it upon a core formed of 
rope which has previously been coated with treacle and 
glue, or glue and whiting, and made perfectly smooth. 
The braiding may be repeated, or a coating of either 
of the solutions may, if necessary, be given, and when 
dry, rolled under pressure with a gentle heat; we finish 
by immersing the whole, and thereby produce the 
'change' and unite all the coatings; the core is after- 
wards removed by boiling in water. For fancy tubing 
the threads may be of various colours. By another 
mode, we take woolen or worsted yarn, of size propor- 
tioned to the strength of the required hose or tubing, 
and saturate and coat it with a solution of caoutchouc, 
gutta percha, or a compound thereof, until the fibres 
are all covered, and when dry we braid it upon a core 
as above; we then roll it under pressure with heat, or, 
if necessary, give it a previous coat or two of either 
of the solutions, and then immerse it to produce the 
'change.' We manufacture these articles also by 
winding these threads or narrow strips spirally round 
the core, keeping the edges quite close, and, if necessary, 
wind another tape or thread over the first in the con- 
trary direction; we then roll them well under pressure 
and heat and immerse them to produce the 'change' 
removing the core as before mentioned." 

It is evident from Hancock's reference to the word 
"change" in his description, that this method of con- 

41 



Rubber in Industry 

struction was in use in Europe after the discovery 
of vulcanization by Charles Goodyear. 

The first rubber hose manufactured in this country 
following the year 1839 was, however, of a different 
character in that it consisted of a long tube of rubber 
incased in a rubber treated fabric jacket and sometimes 
overlaid with a rubber cover. The jackets were 
formed by weaving, on a flat loom, strips of cotton 
fabric the widths of which were proportionate to the 
circumference of the hose desired. These strips were 
afterward impregnated with rubber or some rubber 
compound by a calendering process being subsequently 
wrapped concentrically and one at a time around the 
tube previously placed over a metal mandrel. All plies 
were laid in such a manner that a lapped seam resulted 
and were joined and held in place by substantial copper 
rivets spaced at intervals the length of the hose. This 
was the essential method of manufacture up until the 
year 1877 at which time B. L. Stover designed a cir- 
cular loom upon which could be woven a seamless tube 
of cotton a process which has ever since been employed 
extensively especially in the construction of fire hose. 
In fact, this woven type is very well adapted for hose 
of large diameter and a major portion of the present 
volume in fire and mill hose is today constructed 
after this manner. 

In common parlance, Stover's idea embraces what is 
known as Cotton Rubber Lined hose but many varia- 
tions of the woven jacket idea have been introduced 
including the type known as the multiple woven cover 
in which two or three jackets are woven together in one 
operation, which type is, by the way, of doubtful value. 

42 



Rubber in Industry 

The basic patent of Stover, however, embraces an im- 
portant principle of present day construction. 

While woven jacketed hose was being developed great 
improvements were also being made in the method em- 
ployed for the manufacture of so-called wrapped duck 
hose. It was discovered that by applying the layers of 
rubberized fabric in a continuous piece by winding 
around the tube using cement to hold the plies of the 
wall together that it was not necessary to use rivets or 
other forms of fastening. Thereby, the cost of manu- 
facture was appreciably reduced and the serviceability 
of the finished product at the same time greatly ex- 
tended. The most marked improvement in rubber hose 
construction was, however, the Braided method begun 
in 1908 whereby the cotton reinforcement around the 
tube of rubber compound is applied after the manner 
that ribbons are braided on a Maypole. This method 
is purely a machine process by which it is possible to 
build pieces of any length and for some purposes at a 
considerable increase over the other types in manufac- 
turing efficiency. 

Since, however, all three methods, perfected and im- 
proved, have prevailed it can be said that the manu- 
facture of hose is today divided into three general 
classes, viz., Wrapped Duck, Woven Jacket and Braided 
constructions. There is, however, a further classifica- 
tion which may embody any two of these basic princi- 
ples. In other words, a combination of Wrapped Duck 
and Braided construction is frequently employed and 
thus can we rightly classify hose according to its method 
of construction into four groups. The peculiarities in- 
cident to the manufacture of these types we will treat 

43 



Rubber in Industry 

individually in paragraphs to follow taking each up in 
the order we have mentioned them. 

A volume of considerable size might be written 
concerning the history of the development of these 
hose types, especially, could we gain access to the 
stories of their adaptation to the present day multi- 
tudinous field of usefulness. This information is, how- 
ever, impossible for us to gather and suffice it to relate 
that during the past 25 or 30 years the use of hose has 
been extended into nearly every industrial activity and 
to every quarter of the globe. By way of illustration 
we may mention that today the Goodrich Company 
manufactures more than 40 different purpose grades 
and there are doubtless, others not embraced in 
our list. This company has specialized in the manu- 
facture of rubber hose for 50 years; indeed the 
present reputation which the products of The B. F. 
Goodrich Company enjoy is founded on the brand 
White Anchor one of Dr. Goodrich's very early products. 
White Anchor hose, in fact, enjoys the distinction of 
being the first really serviceable, flexible conductor of 
fluids offered to the trade and this brand name even 
today represents the acme of perfection in hose building. 
This brand is still constructed much the same as it was 
when Mr. Wheeler established for himself such an envi- 
able reputation as the first Goodrich Salesman. 

Today, our Hose Department production facilities, 
which are almost beyond the comprehension of the lay- 
man, represent a steady year by year growth until we 
are considered as ranking first among the companies in 
the United States in volume of output when all types 
are embraced; which growth we may safely claim, is 

44 



Rubber in Industry 

the logical sequence of the good-faith principle of con- 
struction initiated by Doctor Goodrich fifty years ago. 

We realize that production figures when given in feet 
or in fact in any unit, usually mean very little to the 
average layman since so very many different sizes, 
weights, and grades are manufactured; and yet, in 
spite of this we would be remiss should Ave allow 
our previous statement to pass without giving more 
substantial evidence of the magnitude of this division 
of our business. We, therefore, merely mention that 
our daily capacity in all sizes and kinds is more than 
two hundred thousand linear feet, and this production 
figure, we may say, will hardly stand correct much 
longer than it takes to tell. 

Although in keeping with the trend of the times 
standardization in Goodrich hose construction is the 
watchword there is even now a grade in our line adapt- 
able to the conditions of almost any service known in 
which hose may be employed. Our present grades and 
types for various purposes have been steadily developed 
in construction detail in order to produce the most 
efficient and economical results in each field of service. 
They are not theoretical but practical grades worked 
out through extensive study and experimentation. 

Characteristics of Rubber Hose. There are four 
general component parts into which a hose may be 
divided, viz., the tube, the fabric plies, the rubber 
cover and the protective covering, each one of which 
must be especially developed and designed to meet the 
service conditions in each particular kind of applica- 
tion. The first three are always present but the fourth 
may or may not be necessary. 

45 



Ritbber in Industry 

(1) The Tube. Inasmuch as this component part is 
the real container of the fluid it is necessarily always 
present; and the rubber compound of which this part is 
manufactured must as inferred be made up of such 
ingredients as will be best suited to the demands of 
each peculiar service requirement. In other words a 
hose employed for the conveying of domestic liquids 
such as vinegar must be provided with a tube the 
compound of which is entirely free from poisonous in- 
gredients, the tube of oil hose must be so compounded 
as to resist the action of this enemy of rubber, the 
tube of a sand blast hose must be made extremely 
tough so as to resist the abrasion of the swiftly flying 
particles of sharp grit and so on down through the 
40 different purpose constructions. There are, however, 
two general methods employed in the manufacture of 
hose tubes, viz., hand and machine. 

The stock for hand-made hose tubes comes from the 
calendering room in multi-ply flat sheet form which is 
to say, it is composed of sheet rubber that has been 
built up layer upon layer rather than being calendered 
to the required thickness in one operation. This 
method as will be recognized, prevents defects; one ply 
covering up any slight imperfection which might occur 
in another. Tubes from this calendered stock are 
either shaped around mandrels — i.e. smoothly finished 
iron rods or steel pipe approximately fifty feet long — 
or, are formed without the aid of this appliance by a 
system peculiarly all our own, this however depending 
upon the nature of the stock used and the type of hose 
for which the tube is intended. But, regardless of this 
feature, the operation is accomplished much in the 
same way; which is to say that the edges of the flat 

46 



Rubber in Industry 

calendered sheet are brought together in a lapped seam. 
This seam, during the vulcanization process, joins 
firmly together making what is in effect a one-piece 
tube. 

Machine-made tubes are those constructed on the 
standard mechanism known as a "tubing" or "spewing 
machine," a device which in shop parlance is generally 
referred to as a "sausage machine." The stock from 
which machine-made tubes are manufactured does not 
come in calendered sheets but on the contrary is sup- 
plied directly from the mill room in "batch" form; i.e. 
in thick slabs resembling sides of sole-leather. This 
material is cut into strips and fed into the hopper of 
the machine being forced into the form of a tube through 
a slightly heated die by the spiral worm. Recent im- 
provements in the construction of tubing machinery 
have enabled us to advance the art of machine tube 
making until it is now possible to produce hose tubes 
for most purposes which are just as satisfactory as the 
hand-made type and with the added advantage of a 
considerably lowered manufacturing cost. 

In conclusion of this rather brief description of the 
construction of hose tubes, there is one point particu- 
larly which we desire to emphasize and this is the 
necessity of so constructing the tube that a hose with 
a smooth interior surface results, offering as little re- 
sistance as possible to the flow of liquids. Particularly 
so is this an important factor in fire hose where it is 
desirable to maintain the greatest possible nozzle pres- 
sure and velocity. Through the rough inner tube the 
loss of pressure in a fire hose may sometimes reach as 
high a value as 25 pounds in 100 feet, which factor of 
loss develops a serious problem, especially in the smaller 

47 



Rubber in Industry 

cities where the water main pressure is relatively small 
and not supplemented by pumping engines. Hand- 
made tubes are, however, used only in the higher grades 
of large diameter hose such as is employed in fire 
fighting, etc. 

(2) The Fabric Plies. As is the case with many 
other rubber products the strength of hose is pro- 
vided by a fabric carcass. Cotton, on account of its 
ability to undergo the processes which rubber must pass 
through and because it will withstand the heat of vul- 
canization with a minimum loss in tensile strength is 
universally used as the carcass material for this product. 
As before mentioned, however, the manner in which the 
fabric is applied as well as the strength of the carcass 
is in a great measure determined by the pressure to 
which the hose will be subjected. Moreover, selection 
of the proper carcass material for each purpose hose, 
we may further mention, constitutes one of the great 
problems in hose manufacture. This we may perhaps 
better illustrate by citing and explaining the rule in 
wrapped duck construction; which is that the number 
of plies does not by any means indicate the strength of 
the hose. In other words, by skimping on the fabric 
unscrupulous manufacturers may offer at a very low 
relative figure a hose of an equal or even greater num- 
ber of plies which will apparently be indicative of the 
proper quality and strength for the purpose desired, and 
through this practice be able to exploit the trade of 
some jobbers and consumers. Need we mention that 
such a practice of substitution is not worthy of the 
term competition and will in the final analysis, revert 
to that maker's discredit. Light material may, how- 
ever, be used where a flexible, light-weight hose is de- 

48 







Combinaiion 
^Cotton Rubber Lined Type 
Single Jacket Type 




cotton m ##iir 

Rubber Lined Type ^jgj 
Double Jacket Style. ^M 




Braided Type. 




Spra.y . 




Wrapping Air Brake Hose with Wet 

Cloth preparatory to vulcanisation 




rneurrii 




Braiding Machines 
SPECIAL COVERINGS* 




Woven Marlin Jacket 



Asbestos' Wire Wrapped 



Rubber in Industry 

sirable, but such material whenever employed by us in 
the manufacture of a light-weight hose is always of 
sufficient body to qualify for the service desired and 
the hose is sold at a price based according to quality 
and its intended use. 

(3) The Cover. Some types of hose, as for example, 
woven jacketed construction are not supplied with a 
cover of rubber but on the contrary have their fabric 
carcass left exposed without protection of any kind. 
Ordinarily, however, this construction will not suffice 
for the rough usage which hose is given and a rubber 
cover is, therefore, placed around the fabric in order 
that the latter may not come in contact with agencies 
such as rock, oil, steam, water, etc. To better illustrate 
this we call attention to the demands incidental to 
creamery service where hose is continuously subjected 
to the action of water and grease and point out that the 
woven cotton jacket under these conditions would last 
but a comparatively short time. The nature of the 
cover, therefore, must be governed entirely by service 
conditions. It does not, however, necessarily follow 
that the cover stock bears any definite relation to the 
compound as used in the tube; as for example water 
hose used in a packing plant must have a cover com- 
pounded to resist the action of excessive abrasion 
caused by the hose being dragged over cement floors 
and around boxes and barrels ; while the tube may never 
come in contact with anything more injurious than hot 
water and, therefore, may be of a simpler formula. 
Rubber covers are either applied in sheet form by being 
fastened to the end of the duck and wrapped around 
the hose with it; or in tubular form built over the fabric 
carcass through the employment of the regulation tub- 

49 



Rubber in Industry 

ing machine. Covers are usually -st inch in thickness, 
but may be made in any gauge desired. 

(4) Gapping. One advantage in favor of Wrapped 
Duck construction is the fact that being made in 50 
feet lengths, capping for the ends may be applied dur- 
ing the building up process whereas if this feature be 
desired on a section of Braided Hose it must be sup- 
plied after the hose is otherwise completed and cut to 
length. The term capping infers a ring of rubber com- 
pound placed over each end of a length thus covering 
up the plies which would otherwise be exposed. Ex- 
posed plies allow moisture, oil, or other chemicals to 
come in contact with the fabric which acting as a wick 
would carry these liquids on up between the plies in 
time, dissolving the friction and thereby cause the ends 
of the hose to fray or blow out at the couplings. Gapping 
is, however, not always essential and in many instances 
the extra cost incident thereto is not justifiable. This 
latter reason is the more important when considering 
Braided construction because this type is rarely used in 
the length in which it is manufactured, i. e., approx- 
imately 500 feet. 

(5) Protective Coverings. Certain types of hose 
such as pneumatic-tool for example are constantly sub- 
jected to conditions of service where abrasive wear and 
abuse are so severe that the rubber cover does not 
afford sufficient protection. In such instances it may 
be economy to provide some additional protection. This 
feature known as "protective covering," is applied in 
several different styles such as duck, asbestos, woven 
cotton, woven marlin and wire helix. Pieces of old 
sail cloth or other fabric cut into strips and wound 
around the hose constitute the first type of cover and 

50 



Rubber in Industry 

while of questionable value as a protection against 
abrasion these makeshifts usually cause the failure of 
a great deal of steam hose by preventing free radiation 
of the heat from the cover. 

Asbestos while fireproof is not a good heat insulator 
as is commonly supposed, and of very little value when 
used as such. Asbestos coverings therefore, as com- 
monly employed have little or no value. This material 
is, however, an excellent flame resistor and should be 
applied wherever the hose is to be used in extremely 
hot places such as coke ovens, furnace pits, etc. This 
style of covering is merely wrapped around the hose 
and must always be supplemented by wire windings to 
hold it in place. It is not practical to apply an asbestos 
covering intended to adhere permanently without such 
further reinforcement. 

Painted Woven Cotton covering consists of heavy 
strands of cotton yarn woven tightly together around 
the outside of the hose being afterwards coated with 
some form of paint. The paint enters the fiber and the 
openings between the warp and weave and provides a 
certain protection against moisture with its consequent 
deteriorating action; and, being woven the rupture of 
one or more threads will not cause the jacket to unravel 
as is the case when twine is simply wound around the 
hose. This type of covering is a very serviceable pro- 
tection against abuse and where employed a lighter 
hose construction may be used for a given service. 

The woven marlin type of covering is made on a 
circular loom just as are all other types of woven jackets, 
the only difference being that the strands are of hard 
marlin twine. Marlin is an exceedingly strong twine 
treated with tar and other substances which permeating 

51 



Rubber in Industry 

the fibre, make it resistant to the action of moisture to 
a practical degree. Marlin twine is also frequently 
wound around hose but may be easily destroyed by 
the cutting of the cord at one point. 

Wire winding is supplied where hose is to be sub- 
jected to any considerable dragging over rough ma- 
terials and serves as a protection against extreme 
abrasive wear and against kinking. Wire winding 
should not, however, be recommended where the hose 
is likely to be crushed; on account of the fact that a 
bend in this heavy wire will not permit the hose to 
return to its normal shape, thus would it be pre- 
vented from conveying its capacity. There are three 
types of wire commonly used in this style of protection 
viz., round, flat, and half round. The wire is not 
wound closely over the hose but applied in the form 
of open helix with considerable space left between each 
turn. It will readily be seen that in certain places 
such as stone quarries, sky scraper construction, mines, 
etc., that wire winding may perform a very valuable 
service toward prolonging the life of the hose itself. 

The Manufacture of Rubber Hose. As we have 
previously inferred in this chapter, manufacture of rub- 
ber hose is carried on under different processes accord- 
ing to four standard types of construction generally 
classified as Wrapped Duck, Braided Carcass, Woven 
Jacket and Combination. Therefore, in describing the 
variations incidental to the manufacture of these we will 
treat them under the captions as enumerated without 
again referring to classification. 

(1) Wrapped Duck. This hose comprises that which 
is made up with a compounded rubber tube supported 
and strengthened by two or more windings or plies of 

52 



Rubber in Industry 

bias cut woven fabric, held together by an elastic bond 
of "friction" and usually though not always protected 
by an outside layer of compounded rubber. Wrapped duck 
construction is the oldest and commonest method of 
manufacture and is employed in the production of every 
sort of service hose. Although in some fields it is rapid- 
ly being superseded by the Braided type, the wrapped 
method still prevails in the manufacture of a large part 
of the total hose volume marketed today. There are 
several reasons for this some of which will be mentioned 
later; but that we may illustrate our statement, two 
will suffice, viz., these are that some compounds will 
not work well in the braided construction, and special 
purpose sizes may not always be possible to construct 
except in the wrapped duck way, where mandrels are 
the only part of the equipment necessary to change. 

All fabric which forms the supporting walls of this 
type of hose is as may be supposed, purchased accord- 
ing to specifications, predetermined in a great measure 
by what pressure the hose is designed to withstand and 
by the use to which it is to be put. The weight and 
weave depend upon the degree of flexibility desired. In 
other words, if a strong flexible construction is necessary 
as in pneumatic-tool hose a greater number of plies of 
lighter duck will be employed; whereas under con- 
ditions where strength but less flexibility are required a 
heavier duck of lesser number of plies will be employed. 
When the fabric employed is under 8 ounces in weight 
it is termed sheeting but otherwise may be classified 
as a duck. 

All hose fabric after being inspected, tested and 
thoroughly dried, is twice run through the calendering 
process and thereby receives a frictional coating on 

53 



Rubber in Industry 

both sides. Sometimes also an additional "skim" 
coating on one side is given by passing the frictioned 
stock through the calender the third time. This rubber 
impregnated and rubber coated fabric is then cut on 
the bias, into relatively small parallelograms, and these 
spliced together into pieces approximately 50 feet long 
and of a width sufficient to form the number of plies or 
wrappings desired in each particular case. These spliced 
lengths are then wound onto shells and transported to 
the building department ready for use. The next step 
is the preparation of the tube which as previously 
described, may either be hand or machine made. These 
as soon as made are pulled over mandrels and trans- 
ported to a building table where the rubberized fabric 
which is to form the plies and the sheet stock which is 
to form the cover, if such is to be provided, are applied 
in one operation very quickly by simply revolving the 
tube on its mandrel between two iron rollers at which 
time the fabric plies and rubber cover are fed on and 
wind themselves around the tube automatically. These 
are smoothed down and rolled tight by a third pulley 
which is brought to bear upon the mandrel from above. 
The hose is now completed insofar as the building is 
concerned and upon being released is transported to 
another bench where it is again caused to revolve 
rapidly at which time long strips of wet muslin which 
are later to play an important part during vulcaniza- 
tion are wound tightly over the surface. The hose still 
on mandrels is now racked up, loaded on cars, shoved 
into horizontal heaters, so termed, and there subjected 
to the action of live steam under a working pressure 
sufficient to bring about that change between the rubber 
and sulphur which turns the compounds from a sticky 

54 



Rubber in Industry 

mass into a tough resisting product. The wet muslin 
strips during this process serve to hold the various 
component parts in their proper relationship until the 
change has taken place whereby they are fused into an 
integral. Following the completion of the cure the 
muslin strips are unwound, the hose slipped from the 
mandrel and couplings applied whereupon the product is 
ready for the market. Branding is accomplished by the 
use of rubber and metal matrices which have previously 
been applied to the outer surface during the building up 
process. 

Although the manufacture of wrapped duck hose in- 
volves a great deal of hand work and close attention 
its simplicity of construction recommends it to the 
small manufacturer on account of the negligible amount 
of special machinery required in its production. In 
addition to this feature wrapped duck hose is advan- 
tageous because being cured on mandrels, even in the 
richest compounds, a smooth tube offering minimum 
resistance to the flow of liquids etc. is thereby produced; 
a feature which is otherwise not always possible. On 
account of the difficulties attending the handling of 
longer mandrels this construction is limited to lengths 
of 50 feet but in sectional diameter, however, the size 
is virtually unlimited. This is another great advantage 
in favor of the wrapped duck method and the one which 
is doubtless chiefly responsible for a continuation of 
this type in the face of the advantages presented in the 
manufacture of the Braided type. 

(2) Braided Hose, so termed, is that construction 
in which the rubber tube is strengthened and supported 
by plies of braided cotton threads. It may be made in 
one-braid, two-braid, or three-braid construction, ac- 

55 



Rubber in Industry 

cording to the number of times it passes through the 
machine which process of manufacture may be briefly 
described as follows, beginning with the tube. This 
part is of course produced on the standard "sausage" 
machine, in a piece either 250 or 500 feet long the 
whole length being at the same time coiled on a stand 
with a circular revolving top. Because it may have 
occurred to some to inquire how it is that the walls of 
this green, i.e. uncured tube do not collapse at points, thus 
rendering the whole piece unfit for further treatment 
we will, by way of explanation, mention that all during 
the process from the very start a slight air pressure is 
maintained within the tube which serves the 
purpose of the mandrel, keeping the walls distended to 
their normal size and shape. This inflation pressure 
which holds the hose to normal size and shape is in- 
creased to overcome the resistance of the braid after 
the first ply has been imposed. These tubes are first 
fed vertically into the braiding machines from under- 
neath; and spool carriers passing in and out around 
each other according to the same plan as followed in 
braiding a Maypole so feed the yarn as to cover the tube 
with jackets or socks of fabric. There are either 24, 
36, or 48 of these spools according to the cross sectional 
size of the hose desired. Upon completion of the first 
braided ply the standard tubing machine is again re- 
sorted to, the tube and single ply of fabric being passed 
through this mechanism and thereby receives a thin 
insulation of rubber compound. As this now partially 
constructed hose issues from this machine it is at once 
wound upon a drum and again taken to the braiding 
reel where the second jacket of cotton fabric is sup- 

56 



Rubber in Industry 

plied, and this procedure is repeated until the length is 
built up to the required number of plies. 

When this point has been reached, however, the thick- 
ness of the last rubber coating is so increased as to form 
not only an insulation for the last braid but as a pro- 
tective covering for the whole hose. An inspection, by 
the way, is made during each step to insure perfection. 
In its now completed form, each length of braided hose 
is run through a tub and there given a dry bath 
of soapstone. At the same time a "cover pricking" is 
given which is to say the hose is passed between spiked 
pulleys which very slightly puncture the cover in almost 
numberless places, thereby destroying air pockets which 
might have formed between this member and the out- 
side braid; a precaution taken to prevent cover blisters 
forming during vulcanization. The soapstone placed on 
the cover is, of course, also a precautionary measure to 
prevent sticking to the mold in which the hose is cured. 

This operation having been accomplished the hose 
wound upon the drum ready for cure is transported to 
one end of a 20-foot hydraulic steam-heated press. Here, 
together with some four or five other similar pieces it 
is drawn through between the jaws where the cure is 
accomplished. This is done section at a time. Air pres- 
sure, of course, is maintained within the hose during 
this step which serves to keep the walk distended to the 
contour of the mold where the cover receives the pat- 
tern desired from a design which has been ma- 
chined on the mold interior surface. 

Braided hose can be manufactured in any length de- 
sired, limited only by the facilities of the factory for 
handling through the various steps. General practice, 
however, se^ms to dictate that for convenience in hand- 

57 



Rubber in Industry 

ling, all sizes of 1 inch and under — inside diameter — 
should be made in 500 foot lengths and in sizes over 
1 inch up to and including 1^ inch inside diameter in 
250 foot lengths. In 2 inch this type is cut into lengths 
of 50 feet and cured on mandrels in open steam hori- 
zontal heaters the same as hose of the wrapped duck 
construction. This variation from usual practice is fol- 
lowed for no other reason than because the demand for 
braided hose in sizes larger than lj inch is so limited 
as yet to make impractical the installation of machinery 
for the handling of these larger sizes in greater lengths. 
As mentioned heretofore one principal advantage of 
the Braided type of hose lies in the fact of its being 
strictly a machine-made product. There are, however, 
other advantages; which is to say this type can be fur- 
nished in any length required which eliminates the neces- 
sity for frequent couplings where lengths of more than 
50 feet are desired. Moreover, braided hose is on 
account of the peculiar method of construction used, 
free from kinking and will not become destroyed so 
easily when the cover becomes worn off as will the 
wrapped duck type when the fabric becomes exposed. 
For these reasons alone this type of construction has 
become exceedingly popular; so much so in fact that 
were it not for the advantages presented by the wrapped 
duck method in the construction of odd lots in a wider 
range of diameters and grades it is safe to assert that 
this braided method would entirely supplant the other. 

Tubing, also in small sizes, such as used on tire in- 
flation pumps, gas lamp connections etc., although not 
covered by the general title of hose, is also made accord- 
ing to the same process except that the cure does not 
take place on presses. 

58 



Rubber in Industry 

(3) Cotton rubber lined. Where high pressures are 
to be encountered and where also extreme flexibility and 
light-weight hose are desirable a rubber tube surround- 
ed and supported by a tubular woven cotton jacket, 
either protected or unprotected, is a superior form of 
construction. This type, known as Woven Hose which 
although largely confined to fire-fighting purposes is 
nevertheless, sometimes furnished in small sizes for 
garden or other water hose purposes. Woven jackets 
for hose are also occasionally employed in combination 
with a Wrapped Duck construction. In all cases these 
are woven on what is known as circular loom machines 
which carry the warp, unbroken, around continuous spiral 
filler threads which run from one end of the jacket to 
the other. Any length of jacket may be woven but on 
account of the difficulty involved in handling longer 
sections 50 feet in this country seems to be about the 
limit. Usually, however, when used in connection with 
municipal fire-fighting purposes one jacket is pulled 
into another, thus forming what is commonly termed as 
double cotton jacketed, rubber-lined fire hose. 

In sizes above \" inside diameter, the tube and 
jacket are constructed independently being afterward 
pulled together. In other words, the jacket material as 
it comes from the loom is cut to the proper length, 
treated by a special process to eliminate twist and 
shrinkage. Following this, the rubber lining or tube 
which has been built, semi-cured and coated with a 
plastic rubber backing is pulled into the jacket and 
there given the final cure. This last operation of 
course joins the tube and the jacket into an insepar- 
able unit. 

59 



Rubber in Industry 

In the manufacture of the f" inside diameter woven 
hose a somewhat different procedure is followed in 
that the tube itself, which in this case is always machine- 
made, is fed through the loom from the bottom, the 
jacket thereby being woven directly upon it. This is 
accomplished much in the same manner as the tube is 
fed into the Braided hose machinery. If this size is to 
be a double or triple jacket construction, the extra 
covers are pulled on afterward and are not fastened to 
each other except at the ends where they are clamped 
into the couplings. Herein lies the difference between 
our method of construction and those manufacturers 
who exploit a type known as Multiple Woven Cotton 
Jacketed hose which combines the two or three jackets 
into one simultaneously woven combination. This lat- 
ter plan of construction is, by the way, extremely more 
costly besides having no advantages to justify the ad- 
ditional expense. 

Cotton Rubber-lined hose, as the product of this form 
of construction is frequently termed, has for ordinary 
uses some disadvantages. Chief among these is that 
the jacket must be thoroughly dried after each period of 
use. Otherwise mildew will gather, causing rapid dis- 
integration. To obviate this difficulty where a woven 
jacket hose is desired above other types of construction 
a rubber cover is sometimes applied over a single light 
weight woven jacket producing what is known to the 
trade as Cotton Rubber-lined and Rubber-covered hose. 
This method of construction gives a light, weather-proof 
hose which needs no drying-out and which is well adapted 
to the requirements of small municipal fire-fighting and 
street-cleaning departments. On the whole, however, 
Woven Jacketed hose for use outside of fire-fighting is 

60 



Rubber in Industry 

more costly than the average traffic will bear. This 
doubtless accounts for the fact that its use today is 
largely confined to fields as just mentioned. 

(4) Combinations of Wrapped Duck and Braided 
or Wrapped Duck and Woven Jacketed constructions 
although not of recent origin in the history of hose 
development are nevertheless, today receiving more at- 
tention than formerly. Probably this is due to the fact 
that these types furnish hose of unusual ruggedness 
adaptable for the especially hard usage met in many 
industrial fields. Combination constructions have the 
added advantage of greater strength and also greater 
flexibility than is possible of attainment where Wrapped 
Duck alone . is used. The weave or braid providing 
extra protection against ply separation, snags or cuts, 
and with the extra advantages of an absolutely smooth 
tube, recommends combination construction hose over 
other types for many severe applications. This 
type of hose is particularly adaptable for air drill, 
boiler Avashout and steam service although it may, 
however, be recommended for any service where the 
expense involved would be warranted. 

The most widely used combination, i.e., Wrapped 
Duck and Braided, is made by first producing an or- 
dinary Wrapped Duck hose of two or more plies, 
covering with compound and then braiding over this one 
heavy ply of cotton reinforcement. The usual rubber 
cover is then applied and the hose vulcanized in the same 
manner as described under Wrapped Duck construction. 
Wrapped Duck and Woven combination is made in the 
same manner except in place of the Braided covering be- 
ing applied over the Wrapped Duck type, a Woven 

61 



Rubber in Industry 

Cotton Jacket is employed. This type is, however, 
very little used. 

The Uses of Hose. To the lay public, hose is not 
often thought of in connection with uses outside the 
garden, lawn, or greenhouse. Yet the application of 
hose to industrial service is so broad in its scope that in 
this brief work it would not be practical to attempt 
more than a mere hint at the places where this important 
rubber article may be found playing an important part. 
Suffice it to mention that hose forms one indispensable 
item of equipment in every plant where water, steam, 
gas, oil, or other fluids are conveyed from point to 
point; and, as we have hinted at in previous paragraphs, 
the conditions surrounding each application sometimes 
determine the type of construction employed and al- 
ways the quality and makeup of the one used. The 
B. F. Goodrich Company has developed over forty dif- 
ferent purpose constructions in order that our product 
may be better fitted to meet all practical needs of con- 
sumers. To give an idea of what these requirements 
are we need but mention that Acid Hose, Air Brake 
Hose, Air Drill Hose, Boiler Washout Hose, Chemical 
Hose, Cider and Vinegar Hose, Coke Hose, Deck Hose, 
Drillers' Hose, Fire Hose, Mill Hose, Garden Hose, 
Gasoline Hose, Hydraulic Hose, Oil Hose, Gas Hose, 
Pneumatic Hose, Radiator Hose, Sand Blast Hose, Spray 
Hose, Squirt Hose, Steam Hose, Suction Hose, Tender 
Hose, Vacuum Hose, Varnish Hose, Water Hose, and 
many others, all require a construction peculiar to the 
service rendered. 

Oftentimes mills and other users will be found pur- 
chasing a grade or type and using it in a service for 

62 



Rubber in Industry 

which it was not originally intended. Naturally, these 
consumers will not be found receiving the value to which 
they are entitled or which they might get by employing 
the right hose in the right place. To many "Rubber 
hose is rubber hose," and the returns which they receive 
from a particular piece in one service they take to be 
an interpretation of the quality of the product which 
may have failed. All failures in service, however, can- 
not be taken as indicative of poor quality in hose con- 
struction for as will readily be seen our highest grade 
of Water hose — White Anchor — which in many cases 
has been found in use for from fifteen to twenty years 
under normal conditions would give out in a very few 
weeks if used for conveying acids or oils. It is, there- 
fore, our mission and our endeavor to educate the 
buyer in the right use of those brands which we as 
specialists have particularly developed for specific pur- 
poses. While it is true that there are a multitude of 
brands, each brand in the Goodrich line indicates a 
construction and moreover each represents a distinct 
development different from all others. 




CHAPTER THREE 

Molded and Lathe-Cut 
Rubber Qoods 

DEFINITION. In its all-inclusive sense, the term, 
Molded Goods would embrace all articles receiving 
their shape and permanence of form in molds on hydraul- 
ically or even hand-operated vulcanizing presses. Full 
molded pneumatic tires, solid tires, hard rubber items of 
many descriptions, boots and shoes of the Hi-press type, 
various sundry items such as bulbs, balls, water bottles, 
etc., are, however, constructed after this general method 
and yet are not embraced within the category of Molded 
Goods in the true factory sense. The term is indeed 
hard to define for it embraces a miscellany of soft rub- 
ber articles outside the Sundries line which are, never- 
theless, of a sundry nature, i.e. for many purposes and 
of many shapes. All, however, are manufactured by 
molding or curing under pressure in so-called cavity 
molds hence the term Molded Goods. 

The widest diversity is represented in the compounds 
used for the manufacture of this line ranging from the 
finest quality of raw rubber as a base to the cheapest 
reclaimed stock and from the softest of gums to com- 
pounds as hard as iron as illustrated by teething rings 
on the one hand and heat-resisting valve rings on the 
other. Naturally the stocks are prepared by many 
different methods depending upon the "flowing" proper- 
ties of the compound and shape of the mold. This 

64 



Rubber in Industry 

feature we will, however, treat later on. But closely 
related to the molded goods line in both manufacture 
and application are those items some of which are 
molded and some not, which because they receive their 
shape after being cured, by sharp knives either hand- 
operated or on lathes are designated by the general 
term Lathe-Cut Goods. 

Historical. If we are to believe the historian, molded 
rubber articles were first made by the South American 
aborigine who used clay for his mold material, some- 
times smearing the latex over the exterior and some- 
times confining it within. Footwear, bulbs, balls, and 
toys were made in this manner but in each case the 
mold was afterward broken to procure the finished article 
in perfect shape. It is true, however, that Thomas 
Hancock of London, England, was the first to begin 
the manufacture of rubber goods on a practical basis 
and it is probably true that the first Molded articles 
were also manufactured by him. At any rate his were 
the first brought to public attention receiving as early 
as 1820 quite general fame in Great Britain. Like all 
other rubber goods, however, these first Molded articles 
had very little commercial value and until after the dis- 
covery of vulcanization could not be manufactured into 
items of permanent shape and form which would remain 
free from stickiness. But immediately this basic dis- 
covery was made the use of Molded rubber articles be- 
gan to expand apace, a movement which has continued 
to grow even to the present day. 

Shortly after his discovery Charles Goodyear granted 
licenses to various manufactories in this country for the 
application of his principle to the manufacture of 

65 



Rubber in Industry 

Molded rubber articles and about the same time, that 
is, 1846, Thomas Hancock took out a patent in Eng- 
land for improvements in the manufacture and treating 
of articles made of caoutchouc, either alone or in com- 
bination with other substances and for the means 
used and employed in their fabrication. This, reduced 
to simple English, translates; for the manufacture of 
compounded rubber articles vulcanized in cavity molds. 
Beyond this brief sketch, a history of the Molded Goods 
line would be of little value in this work if indeed it 
would be possible to compile such data. Suffice it to 
mention that the history of the Molded Rubber Goods 
line is yet in its infancy, and although thousands of 
articles are today manufactured by this method it can 
be said upon competent authority that the possibilities 
are not as yet even known. 

In the United States we have reached our present status 
through a slow period of development beginning with 
about the year 1846; new uses and adaptations being 
discovered, one might say, almost daily. How many 
thousands of articles are today manufactured by the 
Molded process is, however, probably not known for 
many uses have been born, lived their life and died; 
while others have been found which are of lasting benefit. 
The character of the output of any large Molded Goods 
factory we can say is therefore constantly changing 
from month to month, as new items are added and old 
ones dropped ; but today in the Goodrich factory more 
than 27,000 different articles are made by means of 
forcing rubber into cavity molds and there holding it 
under pressure for the duration of the cure. Doubtless 
even as this is being written new items are being added. 

66 



Rubber in Industry 

Characteristics of Molded and Lathe-Cut Rub- 
ber Goods. As previously mentioned Molded and 
Lathe-Cut Goods may be soft and pliable or tough and 
rigid, almost like iron. They may also be of almost 
any shape or size and constructed either wholly or in 
part from rubber compound. They may sell alone as 
items of commerce (witness the heel) or, as is usually 
the case form an accessory part to some machine or 
appliance made and sold by others. All, however, have 
in common one characteristic. By this we mean that 
they represent the manufacture of rubber goods in its 
most elemental form and the steps in construction be 
the item a tackbumper or deckle strap are substantially 
the same from the milling of the compound to the 
cleaning of the finished product. 

Regardless, however, of the character of the article, 
the construction of the molds themselves is a feature of 
vital importance and one which has an important 
bearing not only on the successful carrying on of the 
processes but upon the service which the article itself 
will later give. In fact so important is a proper con- 
struction of mold equipment considered in the manu- 
facture of a Molded Goods Line that we cannot trust 
the average machine shop with the making of such 
equipment. We therefore maintain in our own plant a 
department where the work of Mold building may be 
carefully supervised by men thoroughly skilled in this 
line of mechanical work and who are familiar with the 
characteristics of rubber and the requirements of rub- 
ber mold work. In this connection we may mention 
further that The Goodrich Company has developed the 
art of Mold making to its highest degree of perfection 
having skilled mechanics and die-cutters who are capable 

67 



Rubber in Industry 

of handling the most intricate of patterns. Unlike many 
manufacturers of such a line we believe that a high 
class article cannot be made in a mold not built accord- 
ing to the most scientific and accurate specifications 
and from a grade of material particularly suited to the 
purpose. The process of vulcanizing Molded Goods is 
one of vital importance and must be the result of proper 
temperature kept steady for an exact length of time. 
The success of this depends in large measure upon the 
proper construction of the mold and is a point in manu- 
facture where the experience and reliability of the mold 
maker has its effect in producing a first grade article. 

The Manufacture of Molded and Lathe-Cut 
Goods. Any description of the manufacture of Molded 
and Lathe-Gut Goods properly begins in the washing 
room with the preparation of the basic raw product — 
rubber — and to be entirely complete such a story should 
continue on through a description of the compounding 
and milling together of the rubber and other ingredients 
which are used. Since, however, these materials prepar- 
ation steps have been so often described and since for 
Molded Goods they are virtually the same as for other 
classes of rubber manufacture we will commence our 
description with the shaping of the stock preparatory to 
vulcanization. This step we may mention compares, 
for instance, to the building-up process in the manu- 
facture of hose, belting, or tires. Stocks for Molded 
Goods are not usually calendered being received in the 
building department in batch form and here treated, as 
may be imagined, in various ways depending upon the 
nature of the article to be manufactured. If for a 
rubber roll or other item whose length is several times 

68 



Rubber in Industry 

its breadth and depth, the ordinary tubing machine 
may be employed to considerable advantage. In such 
a case the stock being fed into a hopper and from here 
passed through heated dies as described in previous 
chapters will issue in approximate form. If the article 
is to be a heel or a valve disc the stock may be also 
run into lengths on the tubing machine and afterwards 
cut mechanically, or even by hand into pieces roughly re- 
sembling the shape of the finished article. Again the 
stock may be calendered on a small mill to the required 
thickness and pieces punched from the resulting slab by 
dies either hand or mechanically operated. 

From here on, however, the process in Molded Goods 
manufacture takes a more uniform course in that the 
raw gum whatever the nature of the finished article, 
must be made to conform in weight exactly to that of 
the completed unit. This step, as we will show, is of 
the utmost importance in maintaining a uniformity of 
product. In other words it will be recognized that 
economical factory practice does not permit of exactness 
in calendering or cutting such stocks and it should also 
be recognized that unless there is this exactness as to 
the quantity of material used, a considerable spoilage 
would result. Many articles when cured, would be 
undersize due to the fact that an insufficient quantity 
of material was used and then again, an excessive 
"overflow" would result from the use of too great a 
quantity. Therefore, in nearly every instance each 
piece before it is allowed to proceed to the next step in 
the process is weighed and trimmed that exactness may 
be secured. While it may seem that such a procedure 
must necessarily call for a tremendous amount of hand 
labor it has been found to be thoroughly practical 

69 



Rubber in Industry 

from an economy standpoint. Moreover when com- 
pared to the intricate steps which other rubber goods 
must pass through in the building-up, this weighing and 
checking is after all a rather simple procedure. 

Having been trimmed to exact proportions, the 
roughly shaped pieces of raw gum are transported to 
the vulcanizing department and distributed throughout 
the room convenient to the presses upon which they 
are to be cured. Let us imagine for a moment that we 
are in a huge bakery where battery after battery of 
ovens each manned by an expert baker are employed in 
turning out an endless quantity of cakes, cookies, and 
buns. Then we will get some idea of the vulcanizing 
department of the Molded Rubber Goods shop. The 
presses as these ovens are known are in reality steam- 
operated stoves composed of a base, head piece, two 
hollow heated jaws, a hydraulic ram, piping, etc. In 
front of each press is a narrow bench upon which the 
workman may arrange his material and suitable valves 
for controlling the heat and pressure of the jaws. Gages 
are provided which enable the press-man to exactly con- 
trol these two elements for each class of stock being 
cured. Suitable tanks of cold water are provided be- 
tween each battery in case it is required that the molds 
be cooled before the articles may be removed. 

The molds themselves which are usually of two parts 
though sometimes of three or more, are spread open on 
the table directly in front of the press after having been 
first heated for a few moments. If metal parts are to 
form a part of the article these are next arranged on 
suitable pegs or in depressions in one half of the mold. 
The pieces of raw gum are then placed within the 
cavities, the mold put together and sli' 1 into place be- 

70 



Rubber in Industry 

tween the press jaws where hydraulic pressure is brought 
to bear by the ram, squeezing the stock into every 
crevice and corner of the mold cavity. Here it is held 
under an enormous pressure ranging from 15 to 680 
thousand pounds according to the article under con- 
struction, until that change in the rubber has taken 
place which turns it from a sticky, useless mass into a 
tough, resilient article. By way of further explanation 
we may now mention that the duration of this cure varies 
from five minutes to two hours or more according to tem- 
perature, characteristics of the compound, and size of 
article, all factors being worked out to a certainty in 
our laboratories during the experimental stage. 

The impression prevails quite generally that Molded 
Rubber articles are made from molten or liquid material 
as are casting of iron, copper, brass, etc. If therefore, 
any of our readers have heretofore entertained this im- 
pression the preceding description although not by 
any means complete in detail; should serve to correct 
this perfectly natural error. Vulcanized articles of this 
class, however, upon being removed from the mold do 
somewhat roughly resemble an unfinished casting in that 
there is always present a rind or fin occasioned by the 
overflow of material through the joints where the mold 
pieces come together. The mold by the way, may con- 
tain one cavity or several dozen depending upon size 
of article, etc. 

The rinds on rubber goods as on castings must 
of course, in turn be removed before the article can be 
said to be complete. This is done in a variety of ways 
depending upon the size, shape, and general character 
of the item and the quantities in which it is manufac- 
tured. Imagination, however, should assist our readers 

71 



Rubber in Industry 

in coming to the conclusion that where very small 
quantities of special items are manufactured the 
trimming must ordinarily be done by hand, whereas 
where quantities are large and production constant, 
machinery can be designed and used in this operation. 
Such at least is the case and regardless of the shape 
of the article or its size, in every well appointed factory 
where Molded Goods are turned out in quantities, will 
be found a variety of specially designed machinery em- 
ployed in the trimming off of the rind or superfluous 
rubber from the cured product. 

This description so far will also apply to the manu- 
facture of lathe-cut goods. Some coming under this 
last category are however not molded, but on the con- 
trary are wrapped with wet muslin tape and cured in 
open steam heaters as is wrapped duck hose. Further, 
the production of "lathe-cut" goods goes one step be- 
yond the trimming off of the rind in that their shape 
and finish are imparted by turning or cutting upon 
lathes. Many such items are cured in lengths being 
afterward cut to small dimensions such as Mason's jar 
rings and printers' feed rollers, while others such as 
typewriter platens are merely turned down to proper 
dimensions. 

Knowledge of rubber compounding gained through 
many years of experience and use of superior materials, 
together with facilities for the manufacture of precise 
mold equipment have brought us to the point where 
we are today enjoying a large percentage of the great 
volume in Molded Goods purchased throughout this 
country. This figure has been estimated at ten million 
dollars annually which if one stops to consider the 
multitude of special requirements including rubber parts 

72 



Rubber in Industry 

of typewriters, pumps, printing machinery, together 
with soles, heels, billiard cushions, etc., will not seem 
an exaggerated figure. On the contrary this will prob- 
ably appear as a rather small price to pay for the thou- 
sands upon thousands of rubber necessities without 
which a great deal of our machinery would literally be 
of no value. 

The Use of Molded Goods. The fact that a great 
percentage of the items constructed by the molded 
process are special in nature makes it difficult in a work 
of this character to give even the remotest idea of the 
extensiveness of such a line. It is in the truest sense 
a made-to-order line, which statement is borne out by 
the fact that nearly 50 per cent of all Molded Goods 
business consists of special items; which is to say of 
items not universally used but which comprise accessory 
parts to machinery, etc. Our chemists are almost con- 
tinually experimenting with compounds to take care of 
demands for new molded rubber articles and our pro- 
duction men are co-operating with them in figuring out 
ways and means for manufacturing such articles at a 
cost which will not be prohibitive. Every day problems 
of this nature are referred to us by geniuses or would be 
geniuses seeking new applications in the field of rubber. 

It would be, however, an impossibility in the brief 
chapter which we have allotted to this subject to give 
anything more than the faintest idea of the multitude 
of uses for molded rubber goods. As mentioned pre- 
viously, in the Goodrich Factory alone over twenty- 
seven thousand articles are embraced within this cate- 
gory and this does not include those which fall under 
the classification of lathe-cut articles. Printing ma- 

73 



Rubber in Industry 

chinery, paper making machinery, plumbing, type- 
writers, automobiles, motors, generators, type setting 
machinery, paper box machinery, bean sorting ma- 
chinery, and in fact, in every walk of present day in- 
dustrial life there are hundreds upon hundreds of 
molded rubber articles used alone or as supplementary 
to mechanical devices. Since therefore, we cannot ex- 
plain the use of the whole list it will have to suffice that 
we give an idea of the requirements of such articles by 
an explanation of a few of the more prominent items. 
(1) A pump is the heart of a circulating system and 
its valves perform the same function as the valves of 
the human heart. An indispensable part therefore, of 
every pump whether it serves to force drinking water 
into city mains or ammonia through an ice plant is its 
valves. The general type is a round rubber disc with 
a hole in the center and in common types of pumps 
there are two sets. These are the suction and discharge, 
controlling the direction of the fluids flow through the 
piping. The "suction" valves cover the suction ports 
lifting to permit the fluid to rise from the reservoir into 
the pump cylinder during the suction stroke and closing 
to prevent its return during the discharge stroke of the 
piston. The "discharge" valves perform the same serv- 
ice; permitting the piston to force fluid out of the 
cylinder into the discharge pipe or service line and 
preventing it from returning during the following 
stroke. The action of pump valves is automatic, be- 
ing controlled entirely by impulses set up by the pump 
piston and the positiveness of their action is provided 
for by spiral springs which react against the impulses. 

The ports or holes over which the valves fit are 
usually provided with grids subdividing each port into 

74 



Rubber in Industry 

several small triangular openings and serving as an 
anchorage for the bolt which hold the valve and valve 
spring in position. The velocity of the flow of the fluid 
and the gritty content of most liquids gradually cut 
away these metal ports causing the valve seats to be- 
come somewhat uneven. Even slight imperfections be- 
tween valve and seat surfaces will cause leakage; which 
progressively and greatly reduces pumping efficiency 
unless a valve material is used that will in some measure 
conform itself to seat irregularities. For this reason 
metal valves are not employed when temperature and 
pressure will permit the use of some flexible material. 
Rubber, balata, leather and other fibrous substances are 
therefore used in the manufacture of pump valves; but 
the distinction of rubber as the most enduring of all 
elastic substances makes it the standard valve material. 
Pressures over 350 pounds per sq. in. and temperatures 
greater than 250 degrees F., however, preclude the use 
of any but metal valves. 

The B. F. Goodrich Company manufactures and offers 
to the trade rubber pump valves in thirty odd grades, 
compounded and constructed to handle liquids under all 
temperatures, pressures, and degrees of purity, within 
the allowable limits. There are soft pliable valves for 
light pressure cold water service and bone hard valves 
for hot water and high pressure pumps. These vary in 
size from a diameter of less than 2 inches by | inch 
in thickness to more than 2 feet in diameter by 3 inches 
in thickness. The smallest are accessory to the small 
high pressure lubricating pumps while the largest are 
used in mine and bilge guard pumps. In addition giant 
high duty pumps are equipped with several relatively 
small valves rather than a few large ones on account of 

75 



Rubber in Industry 

the efficiency of such practice, the most popular size 
being about a 4 inch diameter. 

A reminder that pumping equipment is an essential 
part of every plant and almost every industrial project 
will suffice to disclose the vast possibilities of this 
avenue for the distribution of molded rubber products. 
While it is true that centrifugal or turbine pumps are 
replacing the piston type in many places and that these 
do not require valves it is also just as true that there 
is a well defined field of application for the piston pump 
which cannot be occupied by the "invader." The in- 
dustrial use of pumps is yet in its infancy and the out- 
put of the larger manufacturers shows increases in pro- 
duction of piston pumps from year to year, calling for 
ever increasing quantities of rubber valve discs. By way 
of information we may mention that this company 
manufactures and markets more valve discs than any 
other rubber company. 

Since the earliest days of the mechanical era, valves 
have been employed to regulate and control the flow of 
fluids. The first form was, no doubt, the wooden gate 
used to close openings in dams and ditches. Then came 
the spigot to shut off the flow of wine when the decanter 
was filled; and now we have gate valves, safety valves, 
cocks, etc. The gate valve is the most widely used and 
is the type in which rubber plays an important part 
as the closure member. These are flat circular pieces 
with round or oval holes through the center; and are 
mounted in the valve on the lower end of a screw; the 
upper end of which is usually equipped with a hand 
wheel. The action of the screw causes the gate to move 
away from the seat permitting the steam, water, or 
other fluids, to pass, or inversely, to press against the 

76 



Rubber in Industry 

port closing it tightly and effectively shutting off the 
flow. The rubber disc provides against irregularities in 
the edge of the port flanges, caused through the pitting 
of the metal when acids or other injurious elements are 
contained in the liquid which passes through the pipes. 

There are two standard disc valve types, Jenkins and 
Crane, both of which we manufacture in all sizes. Re- 
quirements in valve service vary with the pressure, 
temperature, and nature of fluids, but we have found 
that our standardized disc as made in two grades only, 
for Low duty and High duty service, meets all require- 
ments so effectively that the reputation of Goodrich 
valve discs remains unchallenged. 

(2) The rapid rise in the art of metal stamping has 
created a considerable demand for molded rubber spring 
bumpers for use in connection with stamping presses, 
and this demand is increasing. Sheet steel, aluminum, 
brass, tin, copper, or any other metal which may be 
drawn is today being stamped into a multitude of 
shapes and sizes for many purposes by means of dies. 
One-half of the die is generally attached to the bed of 
the press while the other is fastened to the plunger. In 
certain kinds of stamping work, particularly that known 
as "drawing" with combination dies, rubber pieces are 
usually found at the bottom die for the purpose of 
exerting a constant back pressure and thereby keeping 
the metal tight in the holding ring. Thus wrinkling is 
prevented during the drawing process and when the 
punch is released these pieces of rubber also serve to 
force the holding ring back into its normal position at 
the same time ejecting the stamped piece from the die. 
The diameter and length of the rubber spring is of 

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Rubber in Industry 

course, governed by the thickness of the metal to be 
worked and the depth of the stroke of the press. 

Other rubber spring bumpers which perform the same 
general service in various ways are also almost number- 
less; as for instance, flexible coupling rubber buffers are 
used to correct slight differences in alignment and to 
absorb a portion of the starting shock where motors 
are coupled directly to the shafting of the driven ma- 
chines. Track bumpers in railroad yards or where small 
cars are employed around mines are also employed to 
prevent the moving car from striking at the ends of the 
tracks with destructive force. Spring board cushions, 
steam shovel bumpers, mailing table pads, grindstone 
collars, channeling machine springs and hammer cushions 
are a few of the thousands and one other uses to which 
this type of molded rubber may be put. 

The stock used in any service required of spring 
rubber must possess a high degree of "come-back" 
quality and must be able to withstand continuous and 
frequent compression without the loss of life. A rubber 
band, as we well know being stretched beyond its 
limits of elasticity breaks. The same thing is true when 
a solid piece of the same material is compressed beyond 
the limits of its elasticity; except that the break may 
occur within where it will not at first be evident. Know- 
ing this, the difficulties met in compounding spring rub- 
ber so that the "recovery" feature is always present 
will be obvious; and when we mention that the demand 
made upon us for this product is growing with each 
passing day it will be seen that our chemists and fac- 
tory men have perfected a spring rubber which will give 
service. 

(3) The tremendous increase in the demand for 

78 



Rubber in Industry 



sanitary plumbing has resulted in a marked growth in 
the manufaeture of plumbers' vitreous, enameled ware 
and brass goods, and as is natural an increasingly large 
demand for the various rubber parts which are acces- 
sory to such fixtures. Although these rubber articles 
are usually small and somewhat obscure by virtue of 
their being hidden, the aggregate volume is exceedingly 
large. Plumbers' rubber articles and their application 
is indeed too big a subject to be dealt with in its entirety 
in other than a volume written on this phase of rubber 
manufacture alone. Accordingly, we will mention only 
the most common items manufactured for this market 
merely to convey the impression of the indispensableness 
of rubber to the comfort and safety of mankind in all 
walks of life and the role molded items play. These 
are Fuller Balls, Bibb Washers, Tank Bulbs, Siphon 
Packers, Elbows, Basin and Sink Stoppers, Force Cups, 
Tack Bumpers, and various connecting parts. 

Fuller Balls and Bibb Washers as employed in the 
two principal types of faucets are. however, items with 
which we come in daily contact and accordingly it will 
perhaps be well for us to at least define the use of these 
two. The Fuller Ball is a part of the valve which 
works on the crank principle closing and opening by 
forcing the ball against the seat of the valve. This 
type is employed in water faucets where as soon as the 
hand is removed from the lever the flow of water ceases. 
Bibb Washers may be compared to Valve discs, pre- 
viously described, being simply flat circular pieces which 
compress against the valve seat as the faucet is screwed 
down closing the opening and stopping the flow. Al- 
though as previously intimated, rubber parts are used 
profusely throughout all modern plumbing work the 

79 



Rubber in Industry 

descriptions of the application of these two items will 
serve to illuminate the wide diversity of the uses of 
molded rubber goods and at the same time give an 
idea as to the compounding requirements which must 
be met. 

(4) The development of the molded rubber cushion 
has without question more than any other agency been 
responsible for the present day universal popularity of 
the game Billiards. This is evidenced by the fact that 
this game was introduced into the court of Charles IX 
in France in 1571 and yet attained no great popularity 
until Michael Phelan introduced in 1854 a rubber 
cushion possessing durability and elasticity. Billiard 
cushions were among the first items of manufacture by 
The B. F. Goodrich Company and during this fifty-year 
period of development the Goodrich has been recognized 
the world over as having played an important part in 
popularizing the American Cushion. This statement is 
exemplified, we claim, by the fact that today Goodrich 
cushions are more popular and more widely used than 
ever. Although the cushion itself is somewhat obscured 
by being built into the table and marketed through 
channels not well known of to the general public yet 
there is a tremendous volume in this division of the 
molded goods line. 

We have told throughout the preceding paragraphs of 
this chapter why in the usual run of the molded mechan- 
ical rubber items a variety of constructions and grades 
are demanded to meet different conditions of service. 
This is only slightly less true of the Billiard Cushion 
business, due to the faci that different table builders 
and purchasers have different ideas as to what con- 
stitutes the best type of cushion. The skilled match 

80 



Rubber in Industry 

player demands accuracy, uniformity and an exacting 
degree of speed, while the moderately skilled amateur 
although appreciating accuracy wants more speed than 
the professional. 

To meet these demands we produce two grades made 
up in different styles. These are namely, the all-rubber, 
the cloth backed a cushion with a layer of- fabric vulcan- 
ized on the lower side and, the cloth and wire insert types. 
Although we feel that the last does not possess uniformity 
of structure, accuracy and length of life found present 
in the all-rubber or cloth insert types nevertheless, we 
produce wire insert cushions for the user who believes 
wire necessary in maintaining proper speed. It is not 
our intent to make a catalog of this work nor that the 
reader should be expected to become familiar with 
grades and types in their various applications from this 
necessarily meagre description. We cite these facts 
concerning demands merely for the purpose of familiar- 
izing our readers with the necessity for a close study of 
all sorts of conditions on the part of the manufacture 
of a general line of molded goods. 

We may mention however that the Billiard Cushion 
is one of those items receiving its approximate shape by 
the employment of the standard tubing or "spewing" 
machine. The holes for the wire insert type are made 
simultaneously with the shaping of the stock through 
the use of mandrels built into the die. To produce the 
best wire insert cushion only the best highly tempered 
steel wire may be used and to effect proper adhesion 
of metal to rubber a chemical treatment to the former 
must be given which is only another illustration of the 
problems met and overcome by the successful maker of 
molded goods. 

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Rubber in Industry 

• — — — — — 

(5) So far in our illustrative description of the 
diversity of uses to which molded rubber goods are 
applied we have confined ourselves to those items 
which are supplementary to other devices. In order, 
therefore, to illustrate the other extreme, i.e. the 
domestic use of molded rubber goods we will take the 
Sole and Heel as our next topic for discussion. Just as 
surely as the world's supply of good leather from which 
to manufacture serviceable soles and heels is diminish- 
ing just so surely must shoe makers in time be forced 
to seek a leather substitute. What better material 
could there be than properly compounded fibre made 
with a base of rubber as the binder? Already the use 
of rubber heels has reached enormous proportions as 
evidenced by the fact that over seventy-five thousand 
pairs including the entire O'Sullivan production are 
daily turned out in the molded goods department of The 
B. F. Goodrich factory. Fibre soles, although today 
not universally adopted by shoe manufacturers, will 
without question in time come to be the logical sub- 
stitute as the shortage of good sole leather becomes 
more and more acute as it is surely bound to do in the 
face of the increasing demands for leather in other 
fields. The Goodrich Textan will maintain its place in 
the forefront when fibre soles become supreme; a place 
which this brand even now enjoys in the limited suc- 
cess to which fibre soles have so far attained. 

We have attempted in the few brief pages preceding to 
convey an accurate impression of the problems in com- 
pounding and manufacture which have been met and 
overcome by this company in its enormous output of 
molded goods for every field of usefulness. At the 
same time we have endeavored to amplify the assertion 

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Rubber in Industry 

that the use of molded goods is still in its infancy. If 
we have succeeded, we will have prompted the coming 
generation to seek other and more practical fields for the 
sale of molded goods and through the use of their facul- 
ties they will doubtless henceforth discover more uses for 
rubber than is today even dreamed of. This chapter 
then will not have been written in vain. 




83 



CHAPTER FOUR 

Packings 

INTRODUCTION. Packings are primarily used to 
correct mechanical irregularities in the surfaces of re- 
movable parts of steam chests, pump cylinders and 
similar devices wherein steam, water or other fluids and 
gases are meant to be handled with as little leakage as 
possible. Secondarily, they are used to stuff, or more 
properly, to pack the glands around pistons or rods to 
prevent the escape of the fluid under pressure through 
the sliding joint between the moving piston rod and the 
stationary part. Theoretically a cylinder or chest could 
be made "tight" by simply bolting together the finished 
surfaces of the two metal parts involved. It would be 
supposed that machined surfaces would form a close 
enough contact to effectually retain the fluid. Experi- 
ence, however, has shown that such a joint though pos- 
sible is impracticable in that the metal will soon rust 
and a slight particle of foreign matter will cause the 
joint to leak within a short time. Other than the 
possibility of leaking, the joint could not be easily 
separated since rust would form a porous and tenacious 
binder. To separate a joint after rust has completed 
its destructive work requires a force which is liable to 
mar the parts and render them useless for further service. 
On account of its uselessness, as soon as trouble 
developed at the unions and flanges, it seemed for a 
time that the steam engine, one of man's most important 
inventions, was to be almost valueless. The early en- 

84 



Rubber in Industry 

gineers, however, were not content to throw the steam 
engine on the "scrap heap" as an interesting but worth- 
less experiment and set to work to devise a joint which 
could be broken and reassembled with ease. Packing 
eventually was the outcome. First, we find leather be- 
ing used and for a time it seemed as if this material 
would remain supreme in this field unchallenged. Leath- 
er was easily cut to the shape required; it would com- 
press readily into the irregularities of the metal parts 
and in addition, possessed sufficient tensile strength to 
withstand, for a time, ordinary steam pressure. The 
first fault which worried the engineer in the use of 
leather was the fact that it could not be rendered 
impervious to the action of the fluid within the engine. 
Once the exposed edge on the inside of the cylinder 
became soaked the capillarity of the leather, due to its 
fibrous structure, carried the liquid throughout the pack- 
ing and it quickly rotted. Again man's ingenuity was 
called upon to come to the rescue of his inventions. 

About this time, 1850, rubber was being put forward 
as a "cure-all" for all waterproofing troubles and it was 
but logical for this material to be tried out as a sub- 
stitute for leather packing. It worked and soon all 
engines were provided with rubber packings which 
saved steam, diminished jar and facilitated the opera- 
tion of the machine. Packing cut from sheets of rub- 
ber was found capable of withstanding greater pres- 
sures with greater assurance against blow-outs. Again 
encouragement returned and the further development 
of the steam engine began. At first the steam engine 
was used only to operate mine pumps or to do such 
other work as formerly had been done by animal strength 
and therefore steam pressures only slightly greater than 

85 



Rubber in Industry 

i ■ — — — — ■ 

atmospheric pressure had satisfied all requirements. 
But the possibilities of such tremendous tireless energy 
encouraged the development of machinery of constantly 
increasing capacities and power requirements. In keep- 
ing apace with the demand for more and more power, 
dimensions of cylinders and other parts became enor- 
mous. Thus the engine occupied too much space and 
soon reached a limit beyond which it was not practical 
to go. Since the area of pistons could not be further 
increased the only alternative, after grouping engines 
together, was to increase steam pressure. Thus a 
small engine could be made to do the work of several 
much larger ones and High Pressure Practice had its 
beginning. The end we cannot see. 

Temperature of steam varies with the pressure and 
engines are operated by the expansive force of heat 
rather than by the blowing effect of steam. Although 
the temperature of saturated steam, i.e., temperature 
due at 150 lbs. gauge pressure is 358 degrees F. or 118 
degrees hotter than steam at 10 lbs. gauge pressure it 
is often found expedient to employ a superheater and 
thus again raise the temperature, in some instances, 100 
degrees. It is then called superheated steam. The ef- 
fect of steam at 458 degrees F. (150 lbs. gauge and 
100 degrees superheat) was more than sufficient to 
destroy almost any packing material known at the time 
of the introduction of superheated steam. 

For several years rubber manufacturers had been re- 
questing the entire mechanical profession to submit 
their packing difficulties for solution and various inter- 
esting compounds had been worked out to overcome 
certain difficulties. Gasket packings had been devel- 
oped to withstand the action of acids which had pre- 

86 






Rubber in Industry 

viously been considered active rubber solvents. Oil 
could be pumped using rubber gaskets and packing 
about the pump cylinders. In fact rubber men were 
somewhat "chesty" in their statement, "we can make 
a rubber compound to satisfy any particular packing 
requirement." Steam engineers at their wits' end ac- 
cordingly challenged these rubber chemists to make 
good their statement. Not instantly but exceedingly 
well did our compounding experts evolve a combina- 
tion of ingredients to produce a packing capable of 
withstanding any degree of superheated steam which 
has so far been found necessary to use. From this 
satisfactory solution Goodrich Packing has made step 
by step of progress to meet the exacting conditions of 
various lines of steam enclosures. 

The Manufacture of Packing. Packings are neces- 
sarily furnished in many grades and forms to meet the 
various requirements of this accessory essential to the 
conveying of steam, water, oil, and in fact, all gases 
and fluids. It would, however, be impracticable in a 
work of this nature to even attempt a detailed des- 
cription of the steps involved in the construction of all 
types and grades and it must, therefore, suffice that we 
confine the following discussions to fundamentals which 
concern the construction of all types alike. For the 
! ake of convenience in expression we will classify 
all packing under three general heads, viz., Sheet 
Packing, Square and Round Packing and Com- 
pressed Packing. Each of these is made in several sub- 
types and grades and as may be supposed each general 
type must be constructed by methods peculiar to its 
form and nature, special machinery being employed 

87 



Rubber in Industry 

wherever justified by the volume manufactured. In the 
following paragraphs we will treat the manufacturing 
steps of each general division in the order named, be- 
ginning our description directly after the milling and 
calendering process since these preliminary steps have 
been so well described in other places. 

(1) Sheet Packing is constructed of layers of com- 
pounded stock built up ply upon ply by a calendering 
process and may be made either of rubber compound 
alone or of rubber with cloth insert known as G. I., a 
cloth backing either one or both sides known as C. 0. S. 
and G. B. S. or with a brass wire insert known as B. W. I. 
In these reinforced types the layer or layers of insertion 
or backing are placed in their proper position during 
the building up process the whole being subsequently 
vulcanized into a compact unit between steel plates on 
a flat bed hydraulic press. This gives the surface a 
smooth, or as it is termed in trade parlance, a plate 
finish. But, if a smooth surface is not desired what is 
known as a fabric finish is given by placing, above and 
below, between the metal plates and the uncured stock 
pieces of wet muslin or duck from which the impression 
of warp and weave is secured by the pressure of the 
ram during the cure. Little else need here be told con- 
cerning the manufacture of sheet packing; indeed there 
is little else to tell. The vulcanized product being im- 
mediately ready for the market is merely put up in 
rolls in the size and form in which it comes from the 
press. The reader, however, must not come to the con- 
clusion that because the manufacture of sheet packing 
is such a comparatively simple process that skill is not 
required; for a knowledge of conditions to be met in 
service, a knowledge of rubber chemistry and compound- 

88 



Rubber in Industry 

ing and an ability to apply this intimate knowledge of 
rubber in the compounding and manufacturing steps 
makes all the difference in the world between a success- 
ful and a poor packing. 

(2) The classification, Square and Round packings 
includes not only those which are perfectly square or 
circular, but rectangular and oval shapes as well and 
these may be made either of solid construction or with 
a hollow center. In the former they are made either 
entirely of rubberized fabric or with a core of compound 
reinforced with windings of rubber impregnated fabric. 
The square duck solid construction variety is made by 
building up a huge slab of rubberized fabric by impos- 
ing one ply on another until the desired thickness has 
been secured, vulcanizing into a solid unit and after- 
ward cutting by special machinery to widths desired. 
Circular packing whether it be either of the hollow 
center or the rubber core variety, is constructed much 
after the manner of wrapped duck hose in that the 
plies of fabric are secured by a process of wrapping 
either around a mandrel as for the hollow type or around 
the core as for the rubber center type. This construc- 
tion, as may be imagined, is wound with wet fabric and 
cured in heaters much the same as is wrapped duck hose. 
A square, rounded corner packing is also frequently 
made after this mode of manufacture. 

(3) Compressed Packing comprises that type com- 
posed of a fibrous ingredient held together by a binder 
of rubber and is built ply upon ply under an enormously 
high pressure. Goodrich Compressed Packing known 
as "Superheat" is composed chiefly of long fibre asbestos 
plus the rubber binder and other ingredients which are 
necessary. We secure directly from the mines the 

89 



Rubber in Industry 

Feldspar ore from which asbestos fibre is made mil ing 
and refining it in our own plant in order that we may 
insure that the original length of fibre is retained in the 
finished product. This we mix with the other ingred- 
ients required and on a huge mill build up sheets layer 
after layer to the thickness desired, afterward cutting 
the sheet from the rolls in which form it is vulcanized 
on flat bed hydraulic presses. 

Many substitutes for "Superheat" are offered to the 
trade which are made with various other fibres as the 
base, but Superheat Sheet Packing is essentially a 
Goodrich contribution and unequaled as a packing for 
high pressure and superheated steam. On account of 
its nature and the method of manufacture employed we 
do not furnish "Superheat" in rolls but rather in sheets 
50x50, 50x150, and 50x75 inches. 

(4) Although we have indicated in a previous pa a- 
graph that packing is generally classified under three 
groups there is yet another type which we have not 
mentioned. This is that known as "Spiral" packing and 
is generally classified separately although but a 
variation of the square and round construe ions. The 
same general steps in manufacturing are followed as 
described in the construction of square and round pack- 
ing although "spiral" is never vulcanized in slab form. 
On the contrary, both shapes are built to their final 
dimensions and by machinery wound in the form of 
helix over iron poles or mandrels, wrapped with wet 
muslin tape and cured in this manner in horizontal 
heaters coming from the process in the form of long 
spiral springs which are afterward cut to convenient 
lengths and boxed for shipment. There is, however, 
"Lubricated Spiral" packing which is procured by im- 

90 



Rubber in Industry 

mersing the cured spirals in a bath of hot oil, subsequent- 
ly graphiting in an ordinary rotating tumbler. 

Characteristics of Packing. We have mentioned 
in the introduction to this chapter that packing is made 
for a great variety of uses, that is, for securing against 
leakage the glands and unions of high and low pressure 
steam engines and lines, hot and cold water pumps, 
ammonia compressor pumps and piping and for pumps 
and piping in breweries, distilleries, chemical plants, etc., 
where unusual conditions of service are to be met. It 
therefore necessarily follows that the characteristics of 
rubber packing must vary in order to meet these dif- 
ferent conditions of service. Such, in truth, is the case 
and we find that a particular packing which serves the 
purpose well in one installation will be wholly unsuit- 
able for the work required in another. It is not our 
purpose to go at lengths into detail concerning the 
characteristics required under all service conditions. The 
reader, however, will perhaps be able to gain a more ac- 
curate impression of what is required from the manufac- 
turer who pretends to furnish this necessary product to 
meet all sorts of industrial uses if we cite a few examples of 
service requirements mentioning the types of packing 
which are best suited to each. 

In many instances, however, special requirements are 
more theoretical than actual by which we mean that 
the whims and tastes of engineers often have an influence 
upon the type of packing which is used. Some oil well 
men, for example, believe that a wire insert packing is 
positively essential in their line of business whereas, 
as a matter of fact any good all rubber sheet packing 
compounded to resist the action of oi 1 would serve the 

91 



Rubber in Industry 

purpose as well if not better. In the main Sheet Pack- 
ings may be used for general purposes either on hot or 
cold water, compressed air, low pressure steam, am- 
monia compressors or chemical lines and will be found 
serviceable in any climate and free from hardening or 
cracking. Moreover sheet packing if lubricated or in- 
stalled between lubricated joints may be used over and 
over again many times. 

"Superheat" packing is of course especially adapt- 
able to high pressure lines and where superheated steam 
is to be conveyed or used. The very nature of the 
compound renders it heat resisting to a high degree 
making possible the efficient and economical operation 
of any engine where superheated steam is required. 
Superheat packing is, in fact, so scientifically com- 
pounded and the mechanical devices employed in its 
manufacture and cure are so well perfected that uni- 
formity of thickness is possible and ply separation un- 
known. This packing may also be used over and over 
again. Thus it is economical as well as safe. 

The principal field for the application of Square Duck 
Packing commonly known as Hydraulic Packing is the 
plunger end of hot and cold water piston pumps. In 
hot water service such as boiler feed pumps it is ad- 
visable to use a grade constructed of fine duck with a 
high quality friction. This will pay from the standpoint 
of less susceptibility to swelling in addition to the gen- 
eral advantage gained through the longer wearing 
properties obtained by the use of high grade materials, 
since any marked degree of swelling tends to shorten 
the stroke of the plunger which in turn reduces the 
capacity of the pump. Coarse ducks especially in com- 
bination with cheaper friction can be used to advantage 

92 



Rubber in Industry 

only for clear water pumping and where muddy or 
gritty water is encountered the fine duck will show far 
greater efficiency. 

Spiral Packing is used in the same class of service as 
Square Duck, i.e., for packing glands around pistons; 
the spiraled feature, being chiefly advantageous in that 
it facilitates the work of repacking such joints. Lubri- 
cating such packings with oil and graphite naturally 
tends toward a reduction of friction between the mov- 
ing and stationary members of the engine or pump 
and thus more efficient operation is secured. 

Conclusion. As should be obvious even from the 
meagre story of constructions and requirements which 
we have been able to give in the short space allowed 
in this chapter The B. F. Goodrich Company has devel- 
oped from time to time remedies and cures for hundreds 
of packing troubles arising in the engineering field. This 
process of evolution, we may say, is yet by no means 
complete and we are from day to day, successfully 
meeting new demands for steam lines, hydraulic eleva- 
tors, oil pumps, chemical lines, or whatever field of 
application we meet as engineers vary the construction 
details of their machinery in temperature and pressure 
measurements. This system of packing study on the 
part of our trained experts has brought us from a 
meagre beginning to our present status as a leading 
manufacturer in the packing field and is maintaining 
for us this enviable position. 

In conclusion, we may mention that in no phase of 
mechanical rubber goods manufacture is the opportunity 
for deception so pronounced as in the field of packings. 
Scrap fabric is frequently made up in attractive form, 

93 



Rubber in Industry 

packed in neatly labeled containers and sold for more 
than one dollar per pound. Hundreds of fancy types 
have been developed and advertised to meet special 
requirements, selling at high prices, none of which 
have qualities to recommend them for a peculiar service 
over the standardized packings as supplied by Good- 
rich. We, therefore, feel justified in making the as- 
sertion that the Goodrich line embraces types of proven 
value and real worth only, made to meet all conditions 
in industrial service in which packing plays a part. 




94 



CHAPTER FIVE 

Rubber Floor Coverings 

DEFINITION. Rubber Floor coverings falling un- 
der the category of noise-deadening, non-slippery 
and waterproof surfaces are frequently confused with 
linoleums and vice versa. In fact not a few believe 
the terms to be synonymous. Such, however, is not the 
case linoleum being a compounded material of ground 
cork and various other filler ingredients held together 
by a binder of oxidized linseed oil over a base of scrim; 
whereas, Rubber Floor Coverings are compounded from 
various ingredients held together by a binder of vul- 
canized rubber; and are much more durable and satis- 
factory from every standpoint although not so cheap 
nor so widely used as linoleums. Although all rubber 
floor coverings fall under this one general classification 
these are listed under the more descriptive subdivisions 
of Matting and Tiling, which classes in turn are divided 
into perforated and solid mats, interlocking and inlaid 
tilings. Whatever the nature of their makeup and re- 
gardless of cost no other form of flooring so satisfactorily 
meets all requirements as a properly compounded well 
made rubber product. It is not only noiseless and at- 
tractive but sanitary, waterproof, odorless, which last 
linoleums are not, and wear resisting to an extreme 
degree. 

Wood, even the best quarter sawed seasoned oak is 
susceptible to moisture and will swell and shrink be- 
sides being noisy and hard to clean ; vitreous tiling is 

95 



Rubber in Industry 

not only noisy, but cold, easily broken and expensive; 
cement and mosaic floors are cold and hard to walk 
upon; linoleums frequently give off an offensive odor 
and are susceptible to curling and not extremely dura- 
ble. Rubber floor coverings on the other hand if 
properly made are soft and yielding to the step but not 
too yielding; they can be compounded in harmonious 
uniform colors and can be cleansed with soap and water 
without deteriorating in quality and appearance. Many 
cases are on record where interlocking tiling put down 
where extreme service requirements were demanded, such 
as in railroad stations, has outworn all materials from 
wood on up through steel and was still standing in 
perfect condition after a length of service much beyond 
which the other materials were worn entirely through. 

History. Although it is only during late years that 
the use of rubber as a floor covering or flooring material 
has been anywhere near general the idea is not by any 
means new. Thomas Hancock in his personal narrative 
relating of the early trials of the rubber industry refers 
to a patent which he took out in the year 1846 for such 
an item of rubber manufacture. In fact in his book 
the Government patent file itself is quoted and the 
patent number given thus anticipating any doubt which 
might otherwise arise as to the authenticity of the in- 
vention. 

Development of rubber matting has, therefore, ex- 
tended back for a period of more than 70 years beginning 
with about 1846. Rut, rubber tiling, we are told, was 
the idea of Charles Goodyear himself, who directly after 
taking out his patent for the process of vulcanization, 
experimented with, among other things, rubber tiles for 

96 



Rubber in Industry 

i 

floors which he hoped to make as brilliant in color as 
those of mineral, as agreeable to the tread as a carpet 
and as durable as the ancient floor of oak. Little did 
Goodyear think then that the time would come when 
rubber tiling would be recognized as the most satisfac^. 
tory and durable flooring material manufactured. The 
first tiling was, however, of the square block and Mosaic 
designs; the interlocking variety not having come into 
existence until several years later; or at the time the 
New York Belting and Packing Company purchased 
the patent and started its manufacture. 

The B. F. Goodrich Company began the manufacture 
of mats and matting about 1897 and a few years later 
at the expiration of the New York Belting and Packing 
Company's patent we added interlocking tiling to our 
line. From our meagre beginning in this direction we s 
have gradually expanded and developed this department 
until today there is no company better equipped to 
manufacture a product of high quality at a fair price 
than we. And there is no problem of rubber flooring 
requirements so difficult that a solution cannot be found, 
if it exists, by the Goodrich experimental men in charge 
of this division of our product. 

Manufacture of Rubber Floor Coverings. The x 
production of rubber matting and tiling as it is managed 
today by The B. F. Goodrich Company is by no means 
an unimportant process carried on under a hit or miss 
plan. The compounding problems which confront the 
analyst are real ; not only from the standpoint of service 
requirements but from the standpoint of production at 
a cost within range of the markets for such an item. In 
other words, floor coverings of rubber must meet in 

97 



Rubber in Industry 

competition those of all other materials including wood, 
cement, stone, linoleum and various other fibre com- 
positions intended to produce resilient, non-porous, long- 
wearing floors. Moreover, in order to meet these other 
flooring materials on anywhere near an equal price 
footing rubber must necessarily be somewhere near the 
same initial cost. Development, however, in this direc- 
tion has not reached the ultimate and although com- 
pounded floorings are being marketed which approach 
the price of other materials; they contain no new rub- 
ber and but a very small percentage of the regenerated 
variety. These may accordingly hardly lay claim to 
the name of rubber floorings and to this we may add 
that to date manufacturers have been unable to pro- 
duce a first class quality which will compete in all fields 
with other standard materials. And yet, insofar as we 
have progressed in this direction it can be said that 
success has been attained and for many services rubber 
flooring has indeed been found to be the most economical 
even at its relatively higher price. Since the manufac- 
ture of matting and tiling is not conducted by identical 
methods we will explain each separately in the order 
named. 

Assuming that the raw materials have been in- 
spected, prepared and mixed, we find the uncured com- 
pound in batch form as it comes from the milling de- 
partment. Slabs of this stock are next built up by 
calendering machinery to the required thicknesses, 
lengths and breadths, and are rolled up as are other 
calendered gums, on cylindrical shells being transported 
to the press room in this form. Here the stock is un- 
rolled, trimmed to the proper sizes and placed on the 
platen of a huge hydraulic press where it is vulcanized 

98 



Rubber in Industry 

under pressure, receiving at the time its permanent^ 
form and design. 

Matting of this character is generally furnished with 
corrugated, pebbled, knurled, or other style of rough- 
ened surfaces which designs are secured through the 
employment of engraved steel plates pressed between 
the upper surface of the mat and the upper jaw of the 
press. Occasionally it is desirable to have an insert of 
fabric in matting of the cheaper quality in order to give 
it more strength. Where such is the case it is merely 
necessary to calender our stock in two pieces interposing 
a frictioned fabric just prior to the vulcanization so that 
it is cured with and becomes a part of the finished mat. 
Although in some few instances we make a matting with 
a fabric insert this practice we do not recommend, since 
it has been our experience that the slightest abuse tends 
to separate the upper and lower layers of rubber from 
the insert and that it is far better to use an all rubber 
mat of a higher grade gum. 

If the product of this process is to be known by the 
trade as "Solid Matting" it is now ready for the market 
but if, on the contrary it is to fall under the designa- 
tion of "Perforated Matting," then one other operation 
must be performed before the product is considered as 
finished. This is the perforating, i e., the cutting of the 
open-work design so often observed on mats found in 
and in front of elevators, in public entrance halls, on 
stair landings, etc. in stores and office buildings. The 
vulcanized solid mat, therefore, is taken to a long table 
where on the upper surface the design is carefully traced 
in chalk from patterns, the perforating being subse- 
quently done by means of dies and punches especially 
designed and made for this purpose. On account of the 

99 



Rubber in Industry 

• ' 

variety of patterns desired and the impossibility to con- 
struct machinery for each pattern to be cut this work 
we may assume, is usually done by hand. To this we 
may add that mats of this character can be made with 
the firm name, facsimile signature, street address or 
monogram, either in the color of the mat or inlaid in a 
different color. Such designs make excellent advertising 
and are usually in demand for entrance halls, of depart- 
ment stores, office buildings, etc. The backs or bottom 
sides of solid and perforated mats may be made smooth. 
The practice usually followed, however, and the one we 
observe is to cure on pieces of coarse wet fabric pro- 
ducing a roughened surface, thereby insuring that the 
mat will remain stationary on the floor where it is 
used. 

The raw gum for interlocking tiling is calendered on 
small mills to approximate thickness being taken off in 
slabs of convenient size for handling during the punch- 
ing operation which is to follow. These are then re- 
moved to an ordinary type of punch press into which 
they are fed and stamped or punched, after the manner 
of metal, into shapes similar to those in which the fin- 
ished units are to appear. Those roughly formed pieces 
are next placed in multiple cavity molds and the molds 
squeezed between the jaws of hydraulic presses where 
the stock is cured into its final form and shape. 

The units are of two sizes and shapes, the smaller be- 
ing made with four sutures into which are fitted four 
dovetail projections molded to the larger blocks. Thus 
absolutely tight, non-movable joints are formed. We 
can perhaps better illustrate this by mentioning that 
the same system of dovetails and sutures is used on 
puzzles and divided maps such as are used in grammar 

100 



Rubber in Industry 

schools and kindergartens. Interlocking tiling although 
ordinarily made in standard colors may be furnished in 
any hue or shade desired merely by the addition to the 
compound during the milling process of the proper pig- 
ment. From this statement it will, therefore, be seen 
that this type of flooring may be made to harmonize 
with any set decorative scheme or made up in variegated 
patterns and designs to suit the taste. 

Inlaid tiling is constructed of square blocks usually 
about XYi&XYi inches in variously colored combinations, 
pieced together diagonally in checker board array, i.e., 
so that each alternate block is of a different color. Two, 
three, four, or in fact as many colors as may be desired 
may be combined in one piece although the usual prac- 
tice is a combination of but two. These colored blocks 
are as may be presumed, cut from calendered sheets 
of raw compound being pieced together and held in 
place on a long calendered sheet of stock with a fabric 
base as a foundation. To this they are carefully 
cemented with a high grade solution. Subsequently, 
this combination of base and inlaid or overlaid pieces is 
squeezed between the jaws of a hydraulic press under 
enormous pressure at which time the various pieces are 
united firmly together and vulcanized into permanent 
form; a substantial product of practically one piece re- 
sulting. 

Solid and Perforated matting may be made in any 
size and shape and in any thickness between J and 1 
inch inclusive. Length is only limited by desire and 
width by the imitations of the hydraulic presses by 
which it is cured; the widest in general use now being 
sixty (60) inches. This feature is one which recommends 
Solid and Perforated matting for so many miscellaneous 

101 



Rubber in Industry 

uses demanding various shapes and sizes. Interlocking 
tiling can of course, be laid continuously without a 
break over any area of floor space. This product is, 
however, generally, made f inch thick. Inlaid tiling 
is limited in length only by desire and the bounds of 
practicability but in width to 57 inches on account of 
the fact that after vulcanization this type of rubber 
floor covering must be buffed and finished and present 
equipment is such that widths greater than 57 inches 
cannot be handled. 

The Use of Rubber Floor Covering. While we 
are not so bigoted as to make the claim that rubber 
mats, matting and tiling, constitute the ideal flooring 
for every condition of service yet these are adaptable 
to thousands of places where an attractive, noiseless, 
and long wearing material is desired. No other material 
surpasses rubber in excellence of tractive qualities; no 
other floor covering is so noiseless, so durable, or so 
easily cleaned and unless abused rubber mats, matting, 
and tiling, where used in their proper respective fields 
will last for years. The general public is daily becom- 
ing more and more alive to the truth of these assertions 
which statement is exemplified by the fact that so great 
is the demand for Goodrich matting and tiling becoming 
that it requires a separate department the sole efforts 
of which are devoted to the manufacture of these items. 

On account of their durability and safety perforated 
and solid mats are in universal demand for floor cover- 
ing in elevators and entrances to buildings. Small mats 
are used on porches, in front of switchboards, in auto- 
mobiles, around barber chairs, and billiard tables, under 
cuspidors and on stair treads.) Interlocking tiling is 

102 



Rubber in Industry 

found to be particularly suitable material for flooring 
the lobbies of public buildings and especially on account 
of the noiseless and sanitary features this type of floor 
material is to be recommended for use in all rooms of 
hospitals. Interlocking tiling is a superior floor ma- 
terial in the home for bathrooms and kitchens and is 
used advantageously on steamships in places where 
countless feet are almost continuously treading. Gym- 
nasium floors overlaid with this type of rubber floor 
covering are springy and durable, easy to the tread and 
furnish when waxed an ideal surface for dancing. In 
stores and banks where considerable standing is neces- 
sary they are also much appreciated because they add 
greatly to the comfort and efficiency of the worker. 

Inlaid tiling has been used principally in the aisles of 
electric interurban and steam railroad coaches, in Pull- 
man cars, for passageway flooring on steamers and as 
hall runners in hospitals, offices, and other public 
buildings. Unlike printed linoleums, inlaid tiling re- 
tains its luster and brightness the pattern in its original 
form remaining until worn down to the very base. For 
club entrances, vestibules of stores, office buildings, 
hotels, etc., -a center panel inlaid with the name and 
street address is extremely attractive as well as effective 
advertising. This floor covering material can be made 
in various thicknesses and any combination of color 
surface may be had. 

Care of Rubber Floor Coverings. Under normal 
conditions Goodrich rubber floor coverings will last for 
years for the stock is tough and enduring having been 
developed expressly for the service to which it will be 
put. It stands to reason, however, that no rubber 

103 



Rubber in Industry 

matting or tiling, regardless of how good, will stand up 
under abuse and the best will succumb to the attack 
of oil or grease and other natural enemies of rubber. 
Porters and janitors are often careless in the handling 
and cleaning of such floor materials. As a rule, a 
rubber mat is much heavier than one realizes and if 
caught by the corner and dragged will soon tear. Such 
an injury is irreparable. When necessary to move 
rubber mats they should be rolled up, not bent or 
folded, since such treatment will cause them to crack 
and tear. They should be washed with soap and water 
preferably the kind of soap which contains no lye and 
above all rubber mats, matting, and tiling should be 
laid on a firm, level foundation where they will not be 
subject to slipping and bending. 



104 



CHAPTER SIX 

Miscellaneous Articles 

AMONG the almost numberless articles falling under 
the general classification of Mechanical Rubber 
Goods there are many which on account of the special 
procedure followed in their construction, do not fit well 
into any of the conventional groups just previously 
treated. The best, therefore, that we can do with these 
is to classify them as Miscellaneous Mechanical Rubber 
Goods. There are a great many of these; in fact the 
number is so large that it would be impossible to do 
justice to each in the short space which we are allotted 
for this chapter. We will, therefore mention only a 
few of the more important describing their manufacture 
in the briefest possible manner. These are Rubber 
Thread, Rubber Rolls, Deckle Straps and Glazing or 
Channel Rubber. Our description of each will follow 
the same order in which we have enumerated them 
without further introduction. 

Rubber Thread. Nadier, an Englishman, in 1820, 
invented and patented a method for cutting thin sheets 
of rubber into narrow strips or threads. His purpose 
was to secure a material suitable for weaving fabric 
from which he might construct waterproof garments and 
he intended to accomplish this much after the same 
general method as employed in fabricating cloth. Al- 
though on account of the peculiar characteristics of rub- 
ber Nadier's idea was then found to be impractical in 

105 



Rubber in Industry 

the field where he wished it to be applied he neverthe- 
less, through his invention, opened up a field for devel- 
opment which has since played a strikingly important 
part in rubber manufacturing history. Following the 
discovery of vulcanization which gave to rubber both 
life and permanence of form rubber thread was 
soon included in the production of many useful articles. 
Chief among such were golf balls and various articles 
of wearing apparel such as suspenders, garters, belts etc. 
The stocks from which rubber thread is constructed 
vary in quality from pure gum to highly compounded 
mixtures depending entirely upon the use to which the 
thread is later to be put. In the production of this 
important item of rubber manufacture the various 
batches after passing through various preliminary stages 
are calendered into long sheets of the required thickness 
being at the same time wound into liner strips upon 
cylinders and transported to the manufacturing depart- 
ment in this form. 

Here the sheet is first unwound and thoroughly soap- 
stoned, i.e., dusted with talc on both sides that the sur- 
face may be kept from sticking at the same time being 
rewound onto a drum within the folds of a long muslin 
bandage. In this shape it is placed within an open 
steam pot vulcanizer and cured. The cured sheet is 
then taken out of the windings of fabric and rewound 
on a large drum under tension. These drums which are 
approximately eight feet in diameter are in fact part of 
the thread cutting machinery and revolve in front of a 
circular knife which being placed against the rubber 
and itself revolving on an automatically adjusted worm, 
travels from one side of the drum to the other thus 
cutting the thread as it progresses. The result is sev- 

106 



Rubber in Industry 

eral hundred pieces of thread between sixty and seventy 
yards in length. Sizes are varied by changing the worm 
and by using different thicknesses of stock; standard 
diameters ranging from J to -^ inch square. After 
being removed from the drum rubber thread is washed, 
inspected and skeined or wound upon spools ready for 
use. 

Rubber Rolls. For parts accessory to various ma- 
chines and sundry mechanical office appliances, Rubber 
Rolls are preferred in a great many instances to those 
made of steel or other materials and have been used 
since even before the discovery of vulcanization in 1839. 
Indeed, Rubber Rolls are not infrequently necessary to 
the success of the device of which they form a part. 
The R. F. Goodrich Company began making a feature 
of this branch of rubber manufacture in 1882, and through 
improvements in methods and equipment have pro- 
gressed to the point today considered as one of the 
largest Rubber Roll manufacturers in the United States. 
The present demand for Goodrich rolls was not created 
in a day but came only after our experts in research 
and manufacture had proved conclusively their ability 
to meet any and all service conditions under which 
Rubber Rolls must operate. 

Although the paper mill industry constitutes the 
largest outlet for this department and we have made 
remarkable progress in securing a large volume in this 
specific field there are nevertheless, hundreds of other 
uses for Rubber Rolls which we are prepared to meet. 
Ry way of illustration, the more common ones of these 
are for clothes wringers, typewriter and adding machine 
platens, feed rolls for typewriters and adding machines, 

107 



Rubber in Industry 

printing press feed rolls, printers' inking rolls, bean 
sorting machinery, box sealing machinery, tanning 
machinery, garment manufacturing machinery, etc. 

As may be imagined from the nature of their use 
Rubber Rolls are nearly always built on cores of metal. 
The first step, therefore, in construction following the 
preparation of materials and the milling of the com- 
pound is the cleaning of the surface of this core. In the 
manufacture of paper mill rolls which we will describe 
as illustrative of roll manufacture in general, a coating 
of cement is first applied to the metal cylinder or rod 
the first layer of rubber then being imposed by hand. 
This first ply of rubber is so compounded as to cure 
hard thus forming a non-separating base for the softer 
compound afterwards built upon it which procedure is 
only one of the refinements of roll manufacture. 
But — one which is nevertheless necessary to the pro- 
duction of a first class roll, since the softer compound 
necessary for the surface will not adhere permanently 
to the steel core but rather tend to loosen as the stock 
is alternately compressed and released in service. 

All rubber roll stocks are received into the building 
department in calendered sheet form, being reduced to 
thicknesses necessary according to the type of roll being 
covered. From this stock the core is covered ply upon 
ply until the necessary depth of rubber as outlined in 
the specifications has been reached. Steams are butted 
and also staggered, which is to say that in order that 
the compound will be of uniform thickness throughout 
and in order that there will be no joints registering in 
the plies each is the exact width of the roll circumfer- 
ence and when imposed the seam is not permitted 
to register with the previous one. After the building 

108 






Rubber in Industry 

is complete, the entire roll is wrapped with wet 
bandages, placed within the vulcanizer and cured 
to its permanent form, after which operation the 
roll is sometimes placed on a lathe and turned down to 
very exacting dimensions and conditions of smoothness. 
To this we may add that paper mill rolls must vary 
in density and grade according to the ideas of the 
various manufacturers, but the hardness and quality is 
governed to a large degree by the pressure under which 
each is operated, the length and diameter of the core 
and the thickness of the rubber coating. Inasmuch as 
there is a variety of service conditions to be met on a 
single paper making machine it must be seen that the 
different purpose rolls must vary in character according 
to their use. In other words, the press rolls, wringer 
rolls, couch rolls, and suction rolls each perform a different 
service and are accordingly made in a different manner. 
We are prepared to furnish several grades in each type 
covering a price and density range which will meet the 
demands of almost any mill man's desires as well as all 
necessary requirements. 

Deckle Straps. The most universally used type of 
paper making machine — the Fourdrinier — requires two 
square endless rubber straps, varying from 13^x1}^ 
inches to 2^x2^ inches. The purpose of these is to 
prevent the solution of fiber and water, termed pulp, 
from running off the shaping machine "wire" as the 
fiber is aligned and a portion of the water removed 
from it between the machine chest and the rolls. 

These moving rubber parts termed "Deckle Straps" 
are constructed from long narrow calendered strips of 
sheet rubber and frictioned fabric; and with all four 

109 



Rubber in Industry 

sides slightly concave. This special feature permits thf 
strap to be reversed when one edge becomes so worn 
that it will no longer adhere closely enough to the wire 
on the table to give a uniform edge to the paper. Fabric 
insertions placed relatively to each other like the spokes 
of a wheel are built into the construction which is to 
say, no two are parallel to each other nor to the sides 
of the strap. Thus, undue strain at any point is pro- 
vided against while the strap is passing over the deckle 
pulley. Vulcanization is effected in hydraulic presses in 
sections of about 18 feet during wh ch operation the 
concave in the sides is secured and the strap given its 
permanence of form and shape. 

Glazing or Channel Rubber. Vibration soon 
cracks putty and other dough glazing materials making 
them impractical for use around automobile windshields, 
elevator doors, car windows, steamship portholes, etc. 
Therefore Channel rubber is employed wherever window 
glass is subject to constant vibration. In modern office 
building construction, steel is today largely employed 
for the window sash and here also Channel rubber must 
be used since putty will not adhere well to metal. 

Although sometimes molded into short sections from 
sheet stock into patterns to fit various makes of auto- 
mobile windshields, porthole glass, etc., Channel rubber 
is usually produced in long strips. When constructed 
in this form the standard tubing or spewing machine 
is employed batch stock being fed into the hopper 
issuing from the die in shapes approximately resembling 
those desired in the finished product. This is afterward 
cured in multiple molds on hydraulic presses, section at 

110 



Rubber in Industry 

a time. The molds being squeezed down upon the 
stock by the jaws of the press, give the rubber its shape 
and finish which is retained by the vulcanized product. 




Ill 



CHAPTER SEVEN 

Marketing 

Belting, Hose, Molded Goods, Lathe Cut 
Goods, Packing, Floor Coverings, Etc. 

Selling. Goodrich Mechanical Rubber Goods are 
marketed through an organization composed of repre- 
sentatives who are concerned solely with this one 
division of our output. This organization as may be 
imagined, is split into divisions according to products 
sold or channels of trade. Thus, sales of all Mechanical 
Goods to Railroads come under the supervision of a 
division of the organization concerned solely with the 
business we secure from the transportation companies. 
Molded Goods are also marketed through a separate 
division of the organization and Mats, Matting, Tiling 
and Rubber Rolls are marketed through another. 

The field representatives of these various divisions 
covering territories which come under the supervis on 
of our various branches where Mechanical Goods stocks 
are carried are under the supervision of the Managers 
of the several branches. Rranch Managers in turn are 
made responsible for the sale of Mechanical Goods in 
their territories subject of course to the general rules 
of the corporation and under the supervision of the 
Mechanical Sales Manager at Akron. On account, how- 
ever, of the wide diversity of markets for the mechanical 
line no hard and fast rule can be laid down and main- 
tained for long, relative to supervision of sales. In con- 

112 




Interlocking Tiling 







Wire Drawing Machine No J 




standard. Sin die Conductor. 
Lead Encased. MFCS. 



Flexible, Dup, 
Minin 




Solid, 
Lead 



l 



fflfmij 



Flexible Single Conductor. TwoBraids. 
WeatherprooF MFCS. 



m 



Stranded, Single Conductor. TwoBraids. 
WeatherprooF MFCS 



Solid, Duple; 
We at k 



Stranded, J 
Wed. 



Plain Rub 







llel and Weatherproof 
ine Cable 



(tlMSMglil 



Z e<3 d Press Depi Cab le Press No t. 




■Parallel, 
d.NZ.CS. 



GOODRICH STANDARD 



'el. Braided and 
N.E.CS. 



inductor. Single Braid 
of N.E.CS 



?red Secondary Cable 



Goodrich "Standard" Concentric 
Mining Machine Cable 



Duplex Automobile fighting Cable 



"""" ! "" —' 



MHHB 



Braided Secondary Cable. 




Rubber Pump Valves 




Packing 



Rubber in Industry 

sequence, some representatives from the Mechanical 
Sales Department although making their headquarters 
at one of our various branches are supervised in all of 
their activities by the Akron office. 

Channels of Distribution. The sale of Mechanical 
Rubber Goods is so involved and complicated with vary- 
ing trade conditions that no cut and dried, inflexible rule 
concerning the channels of distribution employed and 
the methods of approach can be followed. In conse- 
quence, to those previously unfamiliar with a line of this 
character, the marketing plans followed often seem con- 
fused and somewhat inconsistent. This is a subject, 
however, to which in the brief space here allotted we 
cannot hope to do justice. We, therefore, merely out- 
line the fundamentals recommending that the student 
of Mechanical Goods Sales gain a further knowledge of 
this subject through a study of the booklets published 
by the Office of the Mechanical Sales Manager on the 
general subject of Sales Suggestions for Goodrich Me- 
chanical Rubber Goods Salesmen. 

As was intimated previously, transportation com- 
panies, paper mills, mining companies, and other large 
industries are frequently sold direct whereas, under 
other conditions the distributor and jobber is relied 
upon as the logical avenue of distribution. Distributors 
frequently and jobbers occasionally are given exclusive 
territories in which they are made responsible for the 
entire sales of Goodrich or Diamond Brand Goods and 
through their own sales representatives dispose of our 
product to mines, mills, hardware dealers, and such. In 
other instances these same selling agencies market Good- 
rich-made Special Brand Mechanical Goods to the trade 

113 



Rubber in Industry 

in competition with our own organization selling our 
Goodrich and Diamond Brand Mechanical products. 
The student may be assured, however, that the dis- 
tributing method employed in each and every instance 
is the result of careful study and intended to accomplish 
but one result; viz., to serve best the ultimate user of 
Goodrich-made products. 

Branch Stocks. In certain instances where indus- 
trial conditions demand such an arrangement in order 
to facilitate distribution of our product our branches 
carry stocks of Mechanical Goods embracing such items 
as have been found most in demand by the industries 
located in their respective territories. The advantages 
to the trade and consumer of having these branch sources 
of supply nearby from which quick delivery may be 
made will be readily apparent. Such stocks permit the 
filling of orders with the least possible delay and it is 
our intention to have them complete enough at all times 
to fill every reasonable immediate shipment order. We 
replenish the supply from the factory from time to time 
as the stocks become exhausted, thereby insuring a well 
chosen assortment at all times in every main center of 
distribution. 

Guarantee. The conditions under which Mechan- 
ical Rubber Goods are used are so beset with chemical 
and mechanical problems and subject to uncertainties 
of care and abuse that very rarely is it possible for the 
manufacturer or seller to guarantee any definite dura- 
tion of life for such products of the rubber factory. 
Since, however, this is the generally accepted principle 
in the field of commerce we need not dwell upon this 
point further than to mention that occasionally manu- 

114 



Rubber in Industry 

facturers are found who are apparently guaranteeing 
their product for definite units of service, in defiance of 
this law. In this connection we desire to voice the 
warning that where such a state of affairs is met with 
by the user, the jobber and retailer of such merchandise, 
we should look for "fire." For no manufacturer of 
Mechanical Rubber Goods, be he thoroughly honest in 
his intentions can afford to go beyond the guarantee 
which we and other responsible companies maintain. 

The R. F. Goodrich Company guarantees every 
product marketed under its own brand names and in 
most instances Goodrich-made private brand goods as 
well to be free from defects in material and workman- 
ship, and to give reasonable length of service in the 
fields where each is intended to apply. Furthermore, 
we protect all consumers of Goodrich and Diamond 
Mechanical Goods against defects in material and work- 
manship and make good whenever from these causes 
our products fail. 

We realize, however, and wish to point out, that there 
are other elements entering into the causes of failure 
besides merely those of workmanship and material. 
Therefore in dealing with the consumer and trade on 
the question of adjustments where failure is met with 
we take these into consideration. Ry this we mean 
that it is recognized that a certain moral responsibility 
rests upon the Company for the recommendations and 
actions of its salesmen. This, however, is a subject 
upon which so much might be told that we cannot here 
give the time and space for thorough treatment. Ac- 
cordingly, we leave this phase of the manufacture and 
sale of Mechanical Rubber Goods to further study on 
the part of the student of this business. 

115 



Rubber in Industry 

The following episode, however, which occurred in 
connection with the beginning of The Goodrich Company 
and White Anchor Hose shows very plainly the spirit 
of fair dealing that has been embodied in our manufac- 
ture of rubber goods from the start, and although it 
has been related many times, a retelling may prove to 
be of interest. 

It seems that one of Akron's celebrities had purchased 
a couple of lengths of White Anchor expecting the 
ordinary, to which he had been accustomed, and was 
surprised at the workmanship. "What d'ye make this 
hose so good for, Doc?" he asked. "None of the other 
fellows do." "Just pure selfishness," was the reply. 
"It makes me nervous to have people kick — and besides, 
I'd lose money in the long run." 

So from the start, because we believed firmly that 
success played no favorites, and all so-called secret ways 
to this goal were largely contained in the ability to 
impress the public of the worth of "worth while" goods 
that we have succeeded in the Mechanical Rubber goods 
field. It is this belief which has ever stimulated The 
Goodrich Company in placing its products on the mar- 
ket, and it is this same belief which has led us to in- 
corporate into the construction of our whole mechanical 
line the best that our experience and knowledge of rub- 
ber permits. In the manufacture of this line we are 
constantly asking ourselves these questions: "Will this 
hose or belt qualify when measured by the Goodrich 
standard?" "Will it adequately take care of the work 
for which it is intended?" "Is it really worth while?" 



116 



INTRODUCTORY 

Insulated Wire 

AS we sit at our desks in a flood of light and tele- 
phone to our friends and business acquaintances, 
or as we ride home on the street car, few of us stop to 
realize what an essential part Electricity and InsuJated 
Wire play in everyday life. Let us, therefore, pause 
just a moment and consider the force which lights the 
lamp, transmits the voice to the listening ear, and rotates 
the wheels of the car— ELECTRICITY. 

Then let us think of the medium through which this 
mysterious force is conveyed from the roaring generators 
at the power house or from the silent storage batteries 
under the seat, to the point where it is converted into 
light or power — WIRE. 

Wire alone, could not transmit the "juice" for other 
bodies have a tendency to rob it of the precious charge. 
Electricity would never reach the lamp, the receiver, 
nor the motor, but would leak out or be stolen before 
it had gone far on its way were it not for the restraining 
influence of that something which supports or is wrapped 
around the wire— INSULATION. 

In the preparation of this section we are at the very 
outset confronted with the most difficult of problems; 
namely, the selection of the material which will be of 
most value to the class of readers whom we are en- 
deavoring to reach. A product so vital to our industrial 
life as Insulated Wire has become presents a subject so 
great that we have always to keep in mind the necessity 

117 



Rubber in Industry 

and inclination of those directly concerned as well as 
our own desire to pass along to others knowledge of the 
subject, which we have gained. The number of suit- 
able topics is far greater than can be well handled in a 
text of this kind however substantial it may be. In 
the selection of our topics we have, therefore, arrived at 
our result by a process of elimination, choosing only 
such as we believe to be of essential interest to those 
this book is likely to reach; whether or not they may 
intend to continue their studies further in this direction. 
To understand any mechanical device clearly one 
must know something of the force with which it is as- 
sociated its use, its requirements and developments; 
hence the chapter on Electricity, its History and Com- 
mercial Application. The very nature of this subject, 
however, is such that anything written concerning it 
may not be comprehended at a glance or by indifferent 
reading such as we generally follow in scanning our 
newspaper. But we believe that everyone should have 
some definite knowledge of the matter treated and 
have bravely disregarded the limits of a few theories 
in order to state the various principles in terms that 
may be readily understood. 




118 



CHAPTER EIGHT 

Electricity 

(Insulated Wire) 

COMPENDIUM. About 2500 years ago students 
observed a certain peculiar phenomena in connec- 
tion with Amber, a substance to which the Greeks had 
applied the name "Elektron." These observations were 
regarded by writers who, as was usual in such cases, 
fell back upon the supernatural for an explanation 
and ascribed to the substance certain mysterious qual- 
ities. Development was so slow that people knew 
practically nothing about electricity up to the beginning 
of the Nineteenth Century. Few discoveries were made 
and such as were, dealt only with electricity at rest 
(static electricity). Although the condenser — that most 
important electrical instrument which now occupies a 
high place in telephony and wireless telegraphy — had 
been devised its use was confined to laboratory pur- 
poses. Almost the only practical electrical invention 
was the lightning rod ; and its usefulness was much over- 
estimated. Nevertheless, electricity was the most ab- 
sorbing topic with which scientific men dallied during 
the Eighteenth Century. It was lectured about and 
demonstrated to large audiences; and was as much 
talked about by everybody as radium or wireless tele- 
graphy have been recently. But still it was merely a 
plaything in laboratories. 

In the last half of the Nineteenth Century, however, 

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Rubber in Industry 

electricity suddenly became "galvanized" into action 
and soon reached a commanding position in the arts 
and engineering. Probably no more spectacular service 
has ever been rendered to the welfare of mankind by 
what practical men like to call "pure science." The 
story of this highly technical development is a most con- 
vincing answer to those who, even now, distrust "pure 
science" and "technical men" as "impractical" and 
"useless." 

What is Electricity? At the very outset we are 
compelled to admit that we do not know what elec- 
tricity is. It is not matter, since it is devoid of physical 
dimensions and weight; yet in its production, trans- 
mission and manifestations it must always be associated 
with matter. Mechanical or chemical energy applied 
to matter at one point may be used to produce elec- 
tricity which may be transmitted to some other point and 
there used to reproduce energy of either kind. Its 
great value to the industrial world exists in this very 
ability to transmit energy instantly great distances and to 
deliver it with minimum loss. Fortunately, however, for 
our purposes a theory is not essential; and although 
our knowledge of this force is restricted to the various 
phenomena which it produces, so are the laws which 
govern the manifestations of many other forces, which 
to the layman seem less mysterious, not well under- 
stood. 

Nomenclature. During the reign of Queen Eliza- 
beth, a certain Dr. Gilbert, an Englishman, carried out 
a series of very remarkable experiments and observa- 
tions upon the then vaguely known properties of mag- 
nets. And, as allied to magnets, investigated other 

120 



Rubber in Industry 

bodies in which powers of attraction could be produced. 
He discovered that this property was by no means con- 
fined to Amber; and in 1600 he enumerated a list of 
several other substances which also possessed it. He 
mentions among others the Diamond, Sapphire, Opal, 
varieties of Rock Crystal, Glass, Fluor Spar, Rock Salt, 
Mica, Sealing Wax, Resin, Jet, Sulphur, etc., and to all 
these bodies in which, like Amber or "Elektron" the 
power of attraction could be produced by rubbing, he 
applied the term "Electrics." From this it was an easy 
transition to the word Electricity. 



ZINC 




CLOTH 



CLOTH 



The Electric Battery — Volta. For nearly two 
thousand years, friction and in- 
duction were the only methods 
known for producing electricity. 
But, in 1786, an unexpected obser- 
cloth vation of the Italian anatomist, 
Galvani, of Bologna, started a 
series of most important discoveries 
and inventions. He observed that 
the legs of frogs which he had been 
dissecting twitched with each dis- 
charge from his static machine. Later he discovered 
by experiment that if strips of two different metals, such 
as copper and zinc, were fastened together forming an 
inverted V, and their free ends applied to frogs' legs 
there were the same nervous twitchings as followed the 
discharge of static electricity. He, therefore, determined 
that electricity was formed through the contact of dis- 
similar metals. Volta, who while investigating this 
question sometime after this invented a chemical 

121 



Rubber in Industry 

method for producing electricity continuously. This is 
now called an electric battery. 

Voltaic Battery. A glass tumbler, with a strip of zinc 
* X fl and a strip of copper dip- 

II ping into dilute sulphuric 

5 ^ y acid is one form of voltaic 

COPPER ce jj an( j w h en several cells 

are combined, they consti- 
tute a battery. With 
slight modifications the 
batteries of today follow 
the general principle de- 
veloped by Volta, and as 
a mark of respect, his 

name is universally used as the unit of electromotive 

force — the "volt." 




Magnetism. Sometime in the remote past one of 
the ancients stumbled over a piece of brown colored 
stone (known to us as magnetic oxide of iron). Upon 
examination, he found that it possessed a peculiar 
property of attracting other small pieces of the same 
material and likewise, particles of iron and steel. 

The Compass. Later the Chinese discovered that if 
a piece of this ore were suspended by a string in such a 
way that its free action was possible, it possessed the 
important property of pointing always in a particular 
direction, nearly North and South; hence they gave it 
the name of lodestone (meaning leading stone) and used 
it in this manner to navigate their ships. 

Artificial Magnets. Lodestone possesses a third im- 
portant property, that of imparting its properties to a 
piece of hard iron or steel when the two are rubbed 

122 



Rubber in Industry 

together, without apparently losing its own original 
force. Compass needles and horseshoe magnets as seen 
in the modern automobile magneto, are practical exam- 
ples of the value of this discovery. Such magnets are, 
however, not made by rubbing the metal upon "lode- 
stone" because its magnetic force is not strong, but by 
the better method of employing electro magnets and 
coils of wire. This will be described later. 

Polarity. The ends of a magnet are termed its 
poles. The end which points toward the North geo- 
graphical pole is generally called the North or plus ( + ) 
pole, while the other end is the South or minus ( — ) pole. 
Just as the male attracts the female, so does the plus 
pole of one magnet attract the minus pole of another 
but, when like poles approach each other the repulsion 
is almost as great in that case as the value of the at- 
traction in the other. Magnets grow stronger and re- 
tain their strength indefinitely when their unlike poles 
are connected by keepers — small bars of soft iron. 

Value of Polarity. The principle of all electric motors 
is based on these attraction and repulsion characteristics 
of magnets. With this fact in mind it will be readily 
appreciated how if a bar magnet be balanced upon a 
pivot where it is free to turn, and the North Pole of 
another strong magnet held in the hand away from, 
but in the path of the first magnet, the South Pole 
of the first will be drawn towards the position of the 
North Pole of the second and the mounted magnet will 
turn on its pivot. If, when it approaches the position 
of the second magnet, the ends of the latter are sudden- 
ly reversed so that its South Pole comes in the vicinity 

123 



Rubber in Industry 

of the South Pole of the swinging magnet the latter 
will be repelled and continue to turn upon the pivot. 
Providing the manipulation of the second magnet is 
properly timed, the first may be caused to revolve con- 
tinuously. 

It was early discovered that if strong magnets were 
employed and the revolving member fixed to a shaft 
the power developed might be used to do work. But 
the strength of permanent magnets of convenient size 
was found insufficient for commercial purposes. So the 
introduction of the electric motor was delayed for some 
one to invent a stronger magnet of reasonable propor- 
tions and an automatic device for reversing the polarity 
of the fixed magnet. 

Magnetic Force of Electric Current — Oersted. In 1819, 
the Danish physicist, Oersted, made a discovery which, 
because it was the first evidence of a connection between 
magnetism and electricity aroused the greatest interest 
and paved the way for the electric motor. He found 







that when a wire connecting the poles of a voltaic cell 
was held over a compass needle, the north pole of the 
needle was deflected toward the west when the current 
flowed from south to north; while a wire placed under 
the compass needle caused the north end of the needle 
to be deflected to the east. Inasmuch as the compass 
needle indicated the direction of magnetic lines of force 

124 



Rubber in Industry 

it is evident from Oersted's experiment that a current 
must set up a magnetic field at right angles to the con- 
ductor. 



Electro-Magnets. 



Lifting 
Magnet 



From Oersted's discovery, it was 
an easy step for Joseph 
Henry, an American 
school teacher, and 
Michael Faraday, an 
English chemist, both 
of whom in 1831 dis- 
covered that a piece of 
iron assumed the pro- 
perties of a natural 
magnet when placed in 
the vicinity of a cur- 
rent bearing wire, to 
make the first electro- 
magnets by coiling insulated wire about a soft iron core. 

Henry. In recognition of Henry's genius, the unit 
of induction is called the "henry" by the electrical in- 
dustry. The wonderful magnetic hoists now employed 
so generally in the steel industry and elsewhere to move 
steel rails and heavy iron and steel masses are develop- 
ments of Henry's invention. These commercial mag- 
nets are capable of lifting 100 to 200 lbs. of iron per 
square inch of pole face, and yet release the load the 
moment the current is cut off. 




Faraday. For the basic principles of the dynamo, 
motor, electric bell and buzzer, electric gear shift and 
many other such devices we are indebted to Faraday. 

125 



Rubber in Industry 



MODERN ELECTRICITY 

The Telegraph. In 1844, S. F. B. Morse invented 
an instrument based on Faraday's discoveries and, be- 
cause it enabled him to write at a distance — tele-graph, 




The Telegraph ^ 

he named it the telegraph. Now, through the inventions 
of Edison and others we are able to send two messages 
simultaneously in each direction. In other words we 
can send four messages over a single wire at the same 
time. This is called quadruplex telegraphy. 

The Dynamo and Motor. If today we were obliged 
to depend upon batteries for our electric current we 
would not be lighting streets and houses with electric 
lamps, riding on electric cars or driving the great ma- 
chinery in the Goodrich Plant by electric motors. The 
cost of zinc or other metals as a fuel in the voltaic cell 
makes the battery too expensive as a source for large 
quantities of electricity. 

Among other things, Faraday discovered that when 
a coil or bundle of wire is rotated between the poles of 
a permanent or an electro-magnet, a current will be set 
in motion within these coils of the wire which, when 
suitable connections are provided, may be carried out 
through other wires and thus converted into force. So 
was the principle of converting mechanical energy into 
electricity discovered and the dynamo invented, making 
possible the present electrical age. Nevertheless, it was 
left to Edison, Tesla, Westinghouse and others to invent 

126 



Rubber in Industry 



the means by which the current created in the dynamo 
could be made to do mechanical work. Of all these 
later inventions, those of Thomas A. Edison, the direct 
current generator and motor and the Edison three-wire 
balanced system of electricity distribution, are relatively 
the most important. 

Definitions of Electrical Terms. Before we go 
farther it will be well to define briefly the two com- 
mercial forms of electricity which are at present of the 
greatest practical value. The flow of electric current 



"When the magnet is 
moving in and out of the 
coil a current of electricity 
is generated. Thus the 
principle of all generators 
of electricity is illustrated." 
— Robinson. 




may be said to be analogous to that of water and al- 
though at variance with theory, a comparison between 
the flow of water and that of an electric current is not 
in error to such an extent that it may not be used here 
for the sake of clearness. Imagine, if you will, a pipe 
conducting water from one place to another and then 
think of an electric current flowing through or over a 
wire from a battery or generating station to a point 
where it is converted into light, heat or power through 
suitable apparatus. 

127 



Rubber in Industry 

Direct Current. If the flow of current in either of the 
two wires, which are necessary to complete an electric 
circuit, is continuous and constantly in one direction 
the electricity is said to be direct current (D.G.) 

Alternating Current. If, however, the course of flow 
is constantly alternating from one direction to another 
in each wire at frequent intervals, the electricity is 
said to be alternating current (AG.) 

Circuit. It is well to note here, by comparison, the 
difference between the flow of water in a pipe and the 
flow of electricity over a wire. If a pressure be applied 
to water at one end of a pipe and the other end left 
open the water will run out and flow freely, but elec- 
tricity must be provided with both an outgoing and in- 
coming path in order to produce a current to flow; con- 
sequently one always hears the path of electricity des- 
cribed as a "circuit" the word being derived from 
"circle." 

Volt — Ampere. In the case of water, the quantity dis- 
charged at the end of the pipe depends upon the cross 
section area of the pipe and the pressure exerted upon 
the body of water. By way of comparison, the unit of 
pressure of electric current in the wire is the Volt and 
the unit of intensity or of current flow is the Ampere. 
The number of amperes in a circuit depends upon the 
connected load, i.e., size and number of lamps, motors, 
etc. supplied, and determines in a large measure the 
size of wire to be used in making connections. It is 
reasonable that no more current (Amperes) will flow 
through the circuit than that required to do the work 
connected in the circuit. The number of amperes in a 
circuit may be determined by dividing the watts by the 
voltage of the circuit which latter is usually constant. 

128 



Rubber in Industry 

Resistance. The term applied to the force with which 
all materials oppose the passage of an electric current 
is Resistance. Therefore, in converting electric energy 
into any other form resistance must be encountered 
and overcome. The unit of resistance is the ohm and 
the resistance of the average 100 W. lamp is 121 ohms. 

All electrical measurements are based upon these three 
terms — Volt, Ampere, and Ohm; and the equation: — 
I=| (Ohm's Law) expresses their true relationship for 
Direct Current. 

Volt. (E) or Electro-motive force — the Unit of Pres- 
sure. The pressure that will cause one Ampere of 
Current to flow through a resistance of one Ohm. 

Ohm (R). The Unit of Resistance — the Resistance 
which will permit one Ampere of Current to pass when 
one Volt of Pressure is impressed on the Circuit. 

Ampere (I). The Unit of Intensity or Current Flow. 
The intensity of the Current that will flow through a 
Resistance of one Ohm under the pressure of one Volt. 

Watt — Kilowatt. In the case of water the quantity 
discharged from a pipe is known as a certain number of 
gallons. The quantity of electricity passing a given 
point in the electric circuit is measured in terms of the 
Watt (Volts x Amperes) . Thus when we say a lamp 
consumes 100 watts, we mean that 100 watts of elec- 
tricity are required to pass through it every hour in 
order that it may deliver its rated .candle power of 
illumination. When watts are to be considered in large 
quantities 1000 is used as a factor and the unit measure- 
ment is known as the Kilowatt (1000 x Watts) . Thus when 
we speak of the price of electricity as being 10 cents per 
Kilowatt Hour, we understand that the cost of operating 
ten 100 watt lamps for a period of one hour is 10 cents. 

129 



Rubber in Industry 

Transmission of Electric Current. A character- 
istic difference between Direct (D.C.) and Alternating 
(A.G.) current lies in the distance to which each may 
be transmitted. The transmission of direct current 
(D.C.) is restricted to a comparatively small radius of 
a few miles; owing to the enormous cost of the large 
wires required to accommodate the current at the rela- 
tively low voltage to which the generation of direct 
current is limited. The exact limit of the distance to 
which alternating current may be transmitted eco- 
nomically has not been definitely determined but the 
present practice covers hundreds of miles. By the use 
of transformers, alternating current (A.G.) may be given 
any desired voltage. 100,000 volts seems to be the 
practical limit in present high tension practice. The 
higher the voltage impressed, the smaller the wire 
necessary to serve a certain capacity. 

The possibility of generating and transmitting alter- 
nating current had been known for some time but a 
theory for the development of apparatus which would 
efficiently employ and convert it into useful work was 
not discovered until comparatively recent years. The 
ordinary incandescent carbon or tungsten lamp will 
operate on either alternating or direct current of a 
given voltage with good results, but arc lamps and 
motors must be especially designed for each class of 
current. Even the suggestion of an alternating current 
motor was at first scoffed at by such great men as 
Edison, but it is pleasant to know that when George 
Westinghouse invented the present efficient alternating 
current apparatus Mr. Edison was among the first to 
recognize his genius and extend to him the appreciation 
of the world. It was Mr. Westinghouse who made 

130 



Rubber in Industry 

possible the great hydro-electric stations at Niagara 
Falls and various other points, that are converting 
waste water into electric energy which in turn is trans- 
mitted by wire to distant places and there converted 
into useful work. Many evidences of the genius of 
George Westinghouse are to be found in "The Greatest 
Rubber Factory in the World." Our synchronous, 500 
Horse Power induction and D. C. motors, the turbines, 
generators, switchboards and lamps bear the trademark 
of the great institution which he founded. 

Transformers, Alternating current is susceptible to 
many changes and conditions to which direct current 
may not be applied. Most important among these 
is the transformation feature, an apt illustration of 
which is to be found on the automobile employing a 
spark coil. By the spark coil or transformer, we take 
a pulsating or interrupted current of about six volts 
and "step it up" to several hundred times that value 
without employing any moving parts, at the same time 
sustaining very little loss of force. In the high tension 
or high voltage transmission lines radiating from the 
great central stations at Niagara and other points which 
cover almost the entire country with a network of 
wire, a current frequently 100,000 volts or more, is 
transmitted to different points and there shunted 
through the coils of transformers which "step it down" 
producing other relatively harmless lower voltages 
which permit of its commercial consumption freely 
without endangering the lives of those who operate the 
machines. 

The familiar type of transformers are those found 
near the tops of poles in the small cities where they are 
employed to reduce a transmission voltage of about 

131 



Rubber in Industry 

2600 volts to the domestic value— 110 to 220 volt 
limit — in order that the electric light, iron, chafing dish, 
coffee percolator and foot warmer may be used in ab- 
solute safety. The distribution systems in larger cities, 
however, are often placed underground through conduits 
and tunnels for safety, enhancement of scenic value and 
the prevention of service interference, hence trans- 
formers are not so much in evidence in larger centers. 

Wireless Telegraphy. Practically all electrical de- 
velopments as described in the foregoing paragraphs 
have been employed to a great extent in the wonderful 
product of Marconi's genius which has served to save 
the lives of so many of our seafaring people. The term 
"wireless" conveys to the unsophisticated an idea that 
here is the place where wires are not employed. At the 
present time, every great wireless telegraph station 
employs hundreds of miles of wire of various sizes 
and forms to assimilate the force and to conduct 
it to the point, high above the ground, where it leaves 
the aerials or antenna on its trip to Honolulu, Paris or 
Tokio. In fact, the modern wireless telegraph station 
is a network of wires; and but for the advantages of 
the best practical insulating material — vulcanized rub- 
ber — wireless telegraphy would probably never have 
been made possible. 

The Primary Cell and Storage Battery. The de- 
velopment of electrical current from magnetism with 
the dynamo or generator is a most wonderful achieve- 
ment, but the laws governing this phenomena are well 
understood and the process is today highly developed 
and efficient. Concerning the production of current 

132 









Rubber in Industry 




flow by so-called chemical means, as in all forms of 
batteries, comparatively little is known; and as a result 
batteries as a whole are more 
or less inefficient. The entire 
upper field of chemistry is still 
hidden from human intelligence, 
but investigation and research 
are gradually and constantly 
opening up new vistas indi- 
cating the existence of new 
forces and it may be found that 
electricity is only a conducting 
medium for other forces. The 
battery cell is, however, very 
important commercially and 
for us to know something 
application. In the follow- 
ing discussion we will, however, in consequence 
of this lack of facts, be obliged to assume the right to 
advance ideas which have not as yet been wholly ac- 
cepted by science but which have been of inestimable 
value to us in partially clearing up a very cloudy and 
mysterious subject. 

The Primary or Voltaic Battery. All metals may 
be divided into two electrical classes — Positive and 
Negative. A member of one class, such as copper or 
carbon, differs from all members of the other class, as 
zinc or iron, and the molecular activity of one differs 
from that of the other. If a strip of metal of the 
positive class (zinc), is brought into close contact with 
a strip of metal of the negative class (copper), a peculiar 
interexchange of activity between them is set up, in cir- 
cular paths. Then if the two metals be placed in a 



it is, 

about 



Gravity Cell 

therefore, well 
its design and 



133 



Rubber in Industry 




*s 



of 



rubber, glass or earthen vessel in separate positions 
partially or wholly immersed in a weak solution of 
acid and water it will be found that 
the solution will permit the energy to 
pass from one to the other principally 
in one direction. 

To demonstrate, fasten one end of 
a wire securely to the copper strip of 
the cell and upon bringing the other 
end of the wire into and out of con- 
tact with the zinc strip a small spark 
will be evidence of a flow of electricity. 
If the wire from the copper plate be 
Dry Cell attached to one of the binding posts 
a bell and another wire led from the other 
binding post to the zinc plate of the battery cell 
the bell will ring, providing the cell and its plates 
are of ample size. Thus it is reasonable to believe the 
theory correct and to assume that different metals 
possess electro activity of varying nature or strength 
and that the activity of one has an affinity for that of 
the other. We know that if this tendency be properly 
directed it may be caused to produce electric current 
and perform work. One of the metals, in ihis case the 
zinc, will disintegrate when all of its activity is spent. 
Salt water may be used instead of acidulated water but 
the action will be weaker. 

Commercial Batteries. The principal commercial forms 
of voltaic batteries are the dry cell and the Daniell or 
crow-foot cell. The active elements of the dry cell are 
carbon and zinc and the liquid is carried in sawdust or 
other absorbent as it was in Volta's original pile, or 
battery. Dry batteries are used for automobile and 

134 



Rubber in Industry 

motor boat ignition, door bell ringing, etc., where the 
service is intermittent. The crow-foot battery employs 
zinc and copper and is so named because of the shape 
of the zinc element. The electrolyte or liquid used is 
copper sulphate (blue vitriol) and water. It is used 
exclusively for telegraph and other closed circuit serv- 
ice and is capable of delivering a continuous flow of 
electricity for a considerable period of time. 

The Storage Battery. The advent of large, centrally 
located electric generating stations created a demand 
for a more efficient form of chemical generator of con- 
tinuous electric current flow than the voltaic cell. This 
demand arose on account of the unreliability of early 
electrical mechanical devices. To gain the confidence 
and hold the respect of the public it was thus necessary 
to provide against the "dark" of an engine breakdown 
or broken belt. Such batteries are connected across the 
distribution circuits and act only in case of emergencies. 

Storage batteries will only store up and give out 
Direct current; consequently after the date of Westing- 
house's invention of the more efficient alternating cur- 
rent apparatus and its almost universal adoption, it 
seemed that the storage battery was doomed to take 
its place in the past with reciprocating engines, horses, 
low pressure steam and metal vehicle tires. But, some- 
body developed the "wild idea" of increasing the high 
cost of keeping a "flivver" by installing self-starters 
and a greater and more exacting demand immediately 
arose for the storage battery. And thus grew up an 
industry of today to which The B. F. Goodrich Com- 
pany largely contributes with hard rubber jars, insula- 
tors and separators. 

135 



Rubber in Industry 

Types. Storage batteries are of two general classes: 
viz., the Lead Type and the Nickel-Iron Type. The 
lead type was developed by Gaston Plante in 1860, and 
consists of a series of pairs of lead plates supported in 
a sulphuric acid solution. The plates are similar at the 
start but when subjected to the influence of direct cur- 
rent from a generator, one of each pair (the cathode 
plate) is converted into sponge lead and the other (the 
anode plate) is changed to peroxide of lead. Sponge 
lead and peroxide of lead possess different electro 
activity and as long as these two plates retain their 
assumed characteristics, a flow of electric current is 
produced and may be used to operate a motor, to crank 
an automobile engine or to light lamps. When this 
current flow becomes weak, the strength of the battery 
may again be restored by passing a current of a definite 
value from an outside source through it for a time, but 
in the direction opposite to its normal discharge. The 
potential of a lead cell is two volts and its capacity or 
ampere rating varies with the size of the plates. The 
average life of the lead battery is one year. 

The Nickel- Iron Storage Battery. With all forms 
of lead storage batteries there are certain objectionable 
features such as excessive weight, acid fumes and 
deterioration of the plates. Edison endeavored to over- 
come all of these objections by inventing a battery 
immersed in caustic potash solution. The life of this 
battery is indefinite and the fluid used is harmless, but 
the space required and cost of charging are greater; and 
its substantial advantage over the lead type has not 
yet been established. The potential of the cell is about 
one volt or half that of the lead cell. A peculiar feature 

136 



Rubber in Industry 

of the storage battery is that its condition of charge 
may be closely estimated by testing the specific gravity 
of the fluid or electrolyte with a hydrometer. 

The acid resisting quality and the fact that rubber 
is one of the best known insulators of electricity un- 
doubtedly establishes hard rubber as a permanent 
factor in the battery industry which, by the way, has 
reached enormous proportions. Although a very ex- 
pensive substance on account of the high quality of the 
crude necessary for its manufacture and the fact that 
the common grades of fillers may not be employed in 
compounding, no satisfactory substitute for hard rubber 
has yet been introduced. The B. F. Goodrich Com- 
pany contributes in a very substantial manner to the 
industry by supplying the most prominent manufac- 
turers with millions of hard rubber acid container jars, 
covers, vent plugs, separators and supports each year. 
There are several concerns making batteries, but three 
or four large companies manufacture almost the entire 
supply of the United States. 




137 



CHAPTER NINE 
Wire 

(Rubber Insulated) 

CONDUCTORS. The study of various materials 
for conducting or transmitting electricity from one 
point to another began in 1729 when Stephen Gray 
experimenting with electric attraction used, instead of 
a glass rod, a tube into the open ends of which he had 
stuck corks to keep out the dust. Upon rubbing the 
glass tube he was surprised to find that the corks which 
had not been rubbed had nevertheless acquired the 
property of attraction as if the charge generated upon 
the glass had spread upon them. To test this further 
he inserted in the corks long wands of wood or metal 
terminating in balls and found that when the glass was 
rubbed the balls attracted light objects. In place of 
the wands he next tried cords and wires, by which he 
suspended a ball from a glass tube held in a balcony 
above, and found that the ball became electrified as soon 
as the tube was rubbed. Wishing to continue this ex- 
periment at a greater distance than could be obtained 
from his balcony, he was obliged to stretch his cord 
horizontally, and to keep it clear of the ground he hung 
it up at intervals by bits of thread attached to nails in 
posts. Under these conditions he was unable to elec- 
trify the ball and he surmised correctly that the charge 
had escaped by way of the suspending threads. A 
friend who was assisting him suggested that they use 

138 



Rubber in Industry 

a finer thread which would give a smaller path by which 
the charge could escape; and a spool of silk being at 
hand, it was tried with the result that he was able to 
electrify the ball at greater and greater distances up to 
as far as 765 feet. Finally, the silk thread breaking 
under the strain, he tried a fine wire, even smaller than 
the silk, but was enable to electrify the ball and now he 
perceived for the first time that the escape of the charge 
depended, not only upon the size of the suspensions, but 
also upon the material of which they were made. As a 
result of a continuation of these experiments he was 
enabled to arrange in one series all bodies which he 
called conductors and in another those which he knew 
as non-conductors or insulators. 

For current electricity the order of Gray's series is 
reversed. In the light of modern investigation we now 
know that there is no strict dividing line between con- 
ductors and non-conductors and that there is no such 
thing as a perfect conductor nor an absolute insulator; 
but that all bodies offer resistance to the passage of 
electricity. Those that offer the greatest are termed non- 
conductors. Joubert concisely defines good conductors 
as those bodies which when electrified at one point are 
immediately found to be electrified all over. The dif- 
ferent characteristics, therefore, of the various sub- 
stances now employed as conductors is accounted for in 
a property known as resistance. 

Resistance may be defined as an opposing force 
existing in all matter which has to be overcome in order 
to cause a flow of electrical energy. In so doing a 
certain amount of energy is continuously transformed 
into heat so long as the flow of electric energy continues. 

139 



Rubber in Industry 



Resistance in an electric current is somewhat analogous 
to the resistance of water pipes to the passage of water. 







Gray's Experiment 

The greater the length of the conductor the greater 
the resistance, and the greater the cross section of the 
conductor the less is the resistance. As mentioned in 
the previous chapter, the unit of measurement for re- 
sistance is the Ohm, so named from the discoveries of 

140 



Rubber in Industry 



Dr. Simon Ohm, who in 1826, formulated a law which 
exhibits the relation of voltage, current, and resistance. 
It is, therefore, obvious that the resistance of a con- 
ductor of electricity should be maintained at as low a 
value as possible; that the cross section area should be 
sufficiently large to accommodate the current required 
by the motors or lamps served; and, that the material 
of which the conductor is made should offer as little 
natural resistance to the flow of electricity as possible. 
It has taken considerable research and experimenting to 
enable scientists to arrange the various good and partial 
conductors of electricity in the order of their con- 
ductivity as follows: 

Good 

Conductors 

Silver 

Copper 

Aluminum 

Brass 

Platinum 

Iron 

Lead 

Mercury 
The invention of the telegraph in 1844 created the 
first appreciable demand for the transmission of electric 
current by wire over long distances and it then became 
necessary to select a metal, which when drawn into 
wire, would best serve the purpose. Capital to finance 
the construction of early telegraph systems was not 
easily obtained, but fortunately the current necessary 
to operate the small and delicate relays of the telegraph 
set was so little that a relatively poor conductor served 
the purpose fairly well and iron or steel wires were used 

141 



Fair 


Partial 


Conductors 


Conductors 


Compact Carbon 


Water 


Acid Solutions 


Animal Bodies 


Salt Solutions 


Flame 


Living Plants 


Cotton 


Damp Earth 


Wood 




Marble 



Rubber in Industry 

on account of their relative cheapness and great tensile 
strength. The earth was even used in most cases for 
the return conductor in order that the outlay of money 
for wire might be reduced to the minimum. However, 
when the dynamo, motor and electric lamp made the 
commercial use of electricity for light and power pos- 
sible, the demand for wire instantly grew to enormous 
proportions; but the poor conductivity of iron and steel 
barred it for electric light and power work and it be- 
came necessary to select a more suitable metal. It 
was known that silver offered the least resistance of any 
metal to the flow of electricity but its value for electrical 
purposes was not commensurate with its cost. For- 
tunately it was found that the relative cost and adapt- 
ability to wire drawing of copper, as well as its high 
rank in the list of electric conductors made that metal 
admirably suited for the purpose. 

Mr. Edison installed copper wire in the first lighting 
plants and, following his lead, the telegraph and later 
the telephone companies appreciating its efficiency also 
adopted copper as the standard for their lines. The 
copper industry, in appreciation, recently presented to 
Mr. Edison a cubic foot of pure copper upon which a 
brief history of his achievements was beautifully en- 
graved. 

Copper is a metallic element occurring abundantly 
in nature and widely used in many arts. It has been 
worked from the earliest times, and was frequently 
mentioned by writers as early as 4700 years B.C. Pre- 
historic weapons, tools, and ornaments of copper, as 
well as domestic implements remain in profusion to this 
day; and it has been stoutly asserted that this metal 

142 



Rubber in Industry 

was known and used before iron. The Romans ob- 
tained their best copper from Cyprus, an island in the 
Mediterranean Sea, and for this reason the metal was 
for centuries known as Cyprium, later contracted to 
Cuprum and Cuper. 

Although today found widely distributed over the 
earth, the United States produces far more copper than 
any other country the present output being more than 
70 per cent of that of the entire world. Arizona, Mon- 
tana, Michigan and Utah are the principal copper pro- 
ducing states and the most famous mines are the Ana- 
conda, the Boston and Montana, Calumet and Hecla 
and Copper Queen. 

In its natural state, the ore varies greatly in quality 
and for this reason the relatively pure product from the 
Lake Regions of Michigan was the highest priced for 
several years. But, after the refining of copper ore by 
electricity was developed, "electrolytic" as the product 
of this process came to be termed, became the standard 
and since any copper ore may be refined by this process 
the product of any part of the country has ceased to be 
distinctive. Although used far and wide for many pur- 
poses, its greatest application is to be found in the wire 
industry; and therefore the following discussion will be 
confined to the phase of copper production leading up 
to the development of wire. 

Early Industry. The copper mining industry in the 
United States dates from 1719, when a mine was opened 
at Arlington, N. J. Our production was, however, 
relatively unimportant and little felt until the rich 
mines of the Lake Regions were opened in 1864. A 
few years later the mines of Michigan alone produced 

143 



Rubber in Industry 

15 per cent of the copper output of the entire world; 
but Michigan took second place when the series of 
fissures carrying copper and some silver were developed 
near Butte, Montana. The most famous of the Butte 
mines, the Anaconda, opened as a silver mine in 1880 
but soon became the world's greatest copper producer. 

Prospecting. The copper industry is now in a most 
flourishing condition, but the early attempts of the 
pioneers were attended by heart sickening failures and 
great sacrifices. The early prospectors in search for ore 
were guided by the primitive mining implements which 
an earlier generation had left about the spots where 
they had collected mineral from the earth; but as the 
number of "would-be" miners increased the guidance 
afforded by deserted stone hammers, became inadequate 
to meet the requirements so other methods had to be 
resorted to; and finally the method which obtains at 
present was adopted. When the mineralogists, or 
evidence in the shape of out-croppings have indicated 
a copper deposit, borings are made of the whole vicinity 
and the different strata encountered are carefully studied 
and plotted so that the depths of the different deposits 
and their "dip" may be accurately ascertained. It is 
interesting to note that late developments have dis- 
closed the fact that many attempts of our earlier miners 
failed because they did not bore "the last few inches" 
separating failure from success. 

Mining. When an ore deposit is sufficiently ex- 
ploited to assure that it can be worked at a profit, a 
mine is located. Be it known, however, that to ascer- 
tain whether a native deposit of copper will pay re- 

144 



Rubber in Industry 

quires a great deal of time and the expenditure of a 
large amount of money. The system employed in 
mining varies as the percentage of copper to the ore 
necessary to mine for a given tonnage and the neglect 
of this precaution has caused several notable failures; 
expensive plants having been erected only to be later 
sold out at a loss. The mine shafts, where possible, 
follow the "dip" of the lode, thus avoiding the un- 
necessary mining of barren ground to reach the lode 
from the shaft as would be the case if the latter were 
vertical. Shafts are now placed a thousand feet or 
more apart and on the vertical sides of the shafts, "drifts" 
are run out along the lode from 85 to 150 feet apart; 
and from these shafts as starting points all of the lode 
matter possible is broken away and sent to the surface. 

Stamping. Crushed copper rock from the mine is 
taken to the "stamp mill" in center-dump tram cars. 
When the mill is reached the cars are run above the 
rock bins where they discharge directly into the bins 
above the "stamps." To save expense as many opera- 
tions as is possible are performed by gravity, but a 
constant effort is always made to introduce labor saving 
mechanical devices, both underground and on the sur- 
face. Among the devices adopted, it may here be 
noted, belt conveyors and elevators using Goodrich 
belts, occupy quite a prominent position. 

The function of the stamp mill is to crush the rock 
ore fine enough to make possible the separation of the 
copper from the mass. The rock runs over a feed pan 
from the bins into the "mortar" or bowl of the "stamp" 
or "hammer," into which a stream of water is also con- 
stantly flowing. Here the rock is crushed to a size 
small enough that it may be splashed through the 

145 



Rubber in Industry 

screens around the mortar. The larger lumps of copper 
are withdrawn from the bottom of the mortar through 
a tube against a small stream of water, which acts as a 
strainer preventing the lighter material from dis- 
charging with the copper. This method of discharging 
is called the hydraulic system and is utilized at several 
stages of the stamp mill process. There are many 
other operations in connection with the stamp mill but 
all of them are designed particularly for the purpose of 
separating the copper from the rock. After practically 
all the rock and other earthy matter have been separated 
from the copper it is sent to the smelter. 

Smelting. The product of the mine that goes direct 
to the smelter in mass often weighs several tons. The 
largest on record which was taken from the Minnesota 
mine in February 1857, was 45 feet long, 22 feet wide 
at the widest point, had a maximum thickness of eight 
feet, weighed about 420 tons, and was about 90 per cent 
pure copper. This "mass" copper together with the 
product of the stamp mill constitutes what is called 
"Mineral." The product of the stamp mill is not 
pure — the principal impurities found being "vein" rock, 
iron, silver, arsenic, traces of nickel and some others of 
the rarer minerals. The function of the smelter is to 
remove these impurities, and to leave the copper in a 
condition best fitted for the different uses to which it 
will be put — the principal of these being for electrical 
purposes such as wire, where great conductivity is required. 
The form in which it leaves the smelter is indicative of 
the use and when it is known that 7/100 of 1 per cent 
of arsenic in copper will reduce the conductivity of the 
latter 25 per cent, and that arsenic is almost always 

146 



Rubber in Industry 

present in copper ores, the necessity of careful refining 
will be appreciated. 

Upon reaching the smelter all mineral is treated first 
in a melting or a reverberatory furnace, the flame 
passing from the fire box over the copper under a low 
arched roof with a stream of air brought in from below. 
This is an oxidizing process and the slag that is thus 
caused to separate from the copper rises to the surface 
and is drawn off. After the removal of the slag, char- 
coal is thrown on top of the copper and a green hard- 
wood pole thrust into the metal the ignition of which 
results in the removal of the oxygen which has become 
mixed with the copper thus changing the action of the 
furnace from an oxidizing to a reducing process. If the 
reduction is overdone, the charge must be re-oxidized 
and again reduced. Thereupon, the copper is "ladled" 
or run out into molds in which it is formed into "Slabs" 
or "Anodes" for the electrolytic process. 

Electrolytic Refining. Copper derived from copper 
ores generally contains enough impurities to render it 
unfit for electrical purposes unless it is refined elec- 
trolytically. The impurities are of two kinds; first, ob- 
jectionable substances, such as arsenic, antimony, iron, 
etc., which reduce its conductivity; and second, small 
amounts of gold and silver which are desirable to re- 
cover, if possible. The impure copper which has been 
cast into slabs or anodes is now hung in large electrolytic 
tanks filled with a solution of copper sulphate. For 
each anode, a cathode, or thin sheet of pure copper, is 
placed in the tank between the alternate anodes, one 
wire of an electric circuit is attached to a slab or anode 
at one end of the tank, the other wire of the circuit is 
attached to the thin sheet or cathode at the other end 

147 



Rubber in Industry 

of the tank, the intermediate connections made, and a 
strong direct current of electricity is passed through the 
whole. As the current passes the anode is eaten away, 
the pure copper being deposited upon the cathode and 
the impurities settling as a slime to the bottom of the 
tank from whence they are removed from time to time 
and treated according to their value. The slime con- 
tains much gold and silver and the anodes may be en- 
closed in canvas bags which permit the free passage of 
the solution but catch the slime that falls. The cost of 
refining copper by this process is about 746 watts of 
current per hour for each 7 pounds of copper refined. 

"Pitch" The product of the tanks, in the shape of 
heavily deposited cathodes, is taken again to refining 
furnaces where it is melted down and brought to 
"pitch" — that is, to a purity of 99.88 per cent. 

Rolling Mills. The pure copper thus refined is 
melted and cast into "wire" bars, about 5 inches square 
and 5 feet long. In this form it is purchased by The 
B. F. Goodrich Company and sent to the rolling mills 
where it is rolled into round rods, about % mcn or tV 
inch in diameter, in which form it is coiled into bundles 
of convenient size and shipped to the Goodrich factory 
at Akron. The monthly average total of these ship- 
ments to our plant is now 500,000 pounds. 

Wire Drawing. The coiled copper rods as received 
by the factory are sent as called for to the "drawing" 
department where they are first pointed and then fitted 
into a series of chilled steel reducing dies by an expert 
known as the "die setter." He arranges the series, 
spacing them certain distances apart upon the rod to 

148 



Rubber in Industry 

correspond with the locations of the die holders on the 
drawing machinery. The copper rod with the dies 
properly set, is then placed in position on the ma- 
chinery, the several dies being securely clamped in 
their respective holders immersed in soapy water. Be- 
tween each there is a revolving spool or drum around 
which the rod is given a few turns in order to provide 
the necessary friction pull for drawing the rod through 
the various steps, reducing it little by little as it passes 
from the feed to the delivery end of the machine. Copper 
rod from the 34 or -^ inch original diameter as the case 
may be, is thus sometimes drawn by successive opera- 
tions (at least two, more often three) to a diameter as 
small as 1/1000 of an inch. 

Without the soapy water or some such cooling lubri- 
cant, it would be impossible, as may be imagined, to 
continue the wire drawing through its several steps 
with anywhere near like success. Even in spite of the 
constant stream of water and soap which is passing 
over the dies the heat generated by friction is such that 
the process tends to harden the copper thereby reducing 
considerably its conductivity. This undesirable charac- 
teristic is, however, easily counteracted by a subsequent 
step during which the wire, wound on metal drums, 
passes through a water sealed furnace where being sub- 
jected to heat and not air, it is thoroughly reannealed 
to a state of ductility suitable for electrical purposes. 
The rolls of wire enter this furnace on a slowly moving 
conveyor through water, leaving it on the same con- 
veyor through water, the mechanism of the apparatus 
being so constructed and speeded as to enable the 
process to go on continuously. The water jackets, of 
course, prevent oxidation. 

149 



Rubber in Industry 

Tinning. We are all conversant with the fact that 
sulphur is one of the principal ingredients in vulcanized 
rubber but a fact with which we may not be so familiar 
is that a reaction, which lessens the conductivity of 
wire, takes place between copper and sulphur, some of 
which is always present in a free state in every rubber 
compound. It is, therefore, necessary to separate the 
insulation from the bare copper wire and because no 
such action takes place between sulphur and tin we use 
this metal. If a wire is destined to be insulated with 
a rubber compound, therefore, it must first be put 
through an acid bath which thoroughly cleanses it and 
removes all grease, and is then run directly through a 
vat of molten tin, a thin coating of which adheres to 
the wire as it passes. Thus is the copper covered with 
a tin plating which prevents reaction between the copper 
and the free sulphur of the insulation. 

Wire Gauges. From what has been related in the 
preceding chapter, it must be apparent that when wire 
is to be installed to supply a few lamps or a small motor 
the required cross section area is naturally much less 
than if the installation were 100 or 1000 lamps or a 500 
horse power motor. It is therefore a practical necessity 
to manufacture wire in various graduated sizes. These 
wire sizes are designated by numbers corresponding to 
certain wire gauges. It is unfortunate that there are in 
existence four or five such gauges; and that their grad- 
uations do not correspond nor their sizes vary in ac- 
cordance with any fixed rule. In this country the gauge 
in most common use is, however, the American wire 
gauge of the Brown and Sharpe Company. 

No. 1 wire on the B. and S. gauge is very nearly 3/10 

150 



Rubber in Industry 

of an inch in diameter, and the smallest wire, i.e., No. 
40, is about 3/1000 of an inch. There are four sizes 
larger than No. 1, designated as 0, 00, 000, and 0000. 
The No. 10 wire on the B. & S. gauge is just about 
1/10 of an inch in diameter and, if of copper, its resist- 
ance is about one ohm per 1000 feet. As a rule of 
thumb method, by subtracting three from the gauge 
number of any wire, we get the number of the wire 
whose cross sectional area is twice as great, as for ex- 
ample, the cross sectional area of No. 7 is twice that of 
No. 10. 

Circular Measure of Wire. Owing to the errors 
likely to occur from lack of agreement in the sizes of 
the various wire gauges, it is becoming more and more 
the custom among electricians to designate wires by 
their diameters expressed in thousandths of an inch, or 
mils. Indeed, by recent orders of the War Department, 
this has been made mandatory for our army. The area 
of cross section of a wire of one mil diameter is taken 
as the unit for area and called a circular mil. In re- 
ferring to wire sizes the standard of measurement, how- 
ever, must always be stated; as, for example, 100 feet 
of No. 8 B. &. S, meaning of course that it must be 
No. 8 according to the Brown and Sharpe Gauge. 

Stranded Wire. Wires larger than No. 0000 B. & S. 
Gauge, are seldom made solid, but are built up of a 
number of small units of the same size into a "strand"; 
the term wire being retained to designate the individual 
wires of the strand. Strands are usually built up of 
wires of such a size that the total is the same as would 

151 



Rubber in Industry 

be the cross section of a solid wire having the same 
gauge number. 

The stranding is done entirely by machinery, so ar- 
ranged as to apply a minimum pull and twist upon 
each separate wire and yet to form a compact cable. 
Too much twist has an injurious effect on the physical 
characteristics of the wire and inversely, not 'enough 
tension produces a poor cable. Certain well defined 
rules are followed in building up the cable. In other 
words, first one wire is used as the core, six wires being 
wound helically around it; the next layer consists of 12 
wires, the third layer of 18 wires, and so on, each layer 
increasing in number by six. Should an extra flexible 
cable be desired, it is sometimes produced by twisting 
several smaller strands of wire together, later building 
these up by following the same rules of progression as 
were defined for the original stranding. 

The cabling or stranding machinery is composed of a 
series of revolving frames each somewhat resembling 
a Ferris wheel with the spools from which the wire is 
fed, representing the passenger cars. The wire itself 
does not revolve but rather the spools are made to 
rotate around a common center through which the 
wires pass, receiving the twist as each spool in turn 
passes entirely around the axle. This latter, i.e., axle 
is hollow and the core wire being fed from a drum 
placed at one end of the machine, passing through this 
hollow shaft, receives its first layer of wires as it leaves 
the first revolving rack. Additional strands, as many 
as desired, are applied in like manner as the cable pro- 
gresses from one rack of spools to another in the build- 
ing up process. 

152 



Rubber in Industry 

Copper Wire Table, Brown and Sharpe Gauge 

Resistance at 68° F. 



Size of Diameter Ohms per 


Feet per 


Pounds per 


wire 


inches 


foot 


ohm 


foot 


0000 


0.460 


0.00004893 


20,440 


0.6405 


000 


0.4096 


0.00006170 


16,210 


0.5080 


00 


0.3648 


0.00007780 


12,850 


0.4028 





0.3249 


0.00009811 


10,190 


0.3195 


1 


0.2893 


0.0001237 


8,083 


0.2533 


2 


0.2576 


0.0001560 


6,410 


0.2009 


3 


0.2294 


0.0001967 


5,084 


0.1593 


4 


0.2043 


0.0002480 


4,031 


0.1264 


5 


0.1819 


0.0003128 


3,197 


0.1002 


6 


0.1620 


0.0003944 


2,535 


0.07946 


7 


0.1443 


0.0004973 


2,011 


0.06302 


8 


0.1285 


0.0006271 


1,595 


0.04998 


9 


0.1144 


0.0007908 


1,265 


0.03963 


10 


0.1019 


0.0009972 


1,003 


0.03143 


11 


0.09074 


0.001257 


795.3 


0.02493 


12 


0.08081 


0.001586 


630.7 


0.01977 


13 


0.07196 


0.001999 


500.1 


0.01568 


14 


0.06408 


0.002521 


396.6 


0.01243 


15 


0.05707 


0.003179 


314.5 


0.009858 


16 


0.05082 


0.004009 


249.4 


0.007818 


17 


0.04526 


0.005055 


197.8 


0.006200 


18 


0.04030 


0.006374 


156.9 


0.004917 


19 


0.03589 


0.008038 


124.4 


0.003899 


20 


0.03196 


0.01014 


98.66 


0.003092 


21 


0.02846 


0.01278 


78.24 


0.002452 


22 


0.02535 


0.01612 


62.05 


0.001945 


23 


0.02257 


0.02032 


49.21 


0.001542 


24 


0.02010 


0.02563 


39.02 


0.001223 


25 


0.01790 


0.03231 


30.95 


0.0009699 


26 


0.01594 


0.04075 


24.54 


0.0007692 


27 


0.01420 


0.05138 


19.46 


0.0006100 


28 


0.01264 


0.06479 


15.43 


0.0004837 


29 


0.01126 


0.08170 


12.24 


0.0003836 


30 


0.01003 


0.1030 


9.71 


0.0003042 



153 



CHAPTER TEN 
Insulation 

COPPER wire as employed for trolley, telegraph cir- 
cuits and many high tension (high voltage) trans- 
mission lines, supported in the air by glass, porcelain, 
or vitreous insulators, is usually left uncovered without 
even a coating of tin. For practically all other pur- 
poses, however, when the element of danger threatens 
life or property some form of insulation is necessary. 
Many materials, known as dielectrics, are used for in- 
sulation. Scientific investigation has arranged the prin- 
cipal non-conductors in a fixed series in order of their 
dielectric value. 

1. Air. 6. Shellac. 11. Leather. 

2. Glass. 7. Resin. 12. Porcelain. 

3. Paraffin. 8. Silk. 13. Oils. 

4. Mica. 9. Wool. 14. Slate. 

5. (Vulcanized) Rubber 10. Paper. 

and Gutta Percha. 

The character of the insulation depends almost en- 
tirely upon the service in which the wire will be em- 
ployed. Telephone and annunciator cables and some 
distribution circuits employ paper, cloth and braided 
cotton singly or in various combinations. Although of 
stronger dielectric properties, for general use air (1), 
glass (2), paraffin (3), or mica (4), could not be employed 
to insulate a current bearing wire, therefore, practically 
all wires for lighting, power, automobile, telephone and 

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Rubber in Industry 

power plant circuits, submarine cables, etc., are insulated 
by rubber or its first cousin gutta percha. No. 5 then 
heads the list of practical insulating materials. 

Rubber. There are hundreds of grades of rubber 
and the use of each grade produces a different result. 
Realizing that the different grades are frequently almost 
indistinguishable, the importance of correct classification 
of crude rubber at the factory must be appreciated. 
Several carloads of the crude reach The B. F. Goodrich 
Company's Receiving Department every day. That 
part of each shipment which meets our insulated wire 
requirements is assigned to certain bins in a large cool, 
well protected rubber storage warehouse. Our selection 
and classification work is in the hand of a widely recog- 
nized crude rubber expert who personally examines each 
lot. 

Manufacturing. There are four principal types of 
insulated wire, but rubber-insulated is the most im- 
portant and the only type manufactured by The B. F. 
Goodrich Company. Since in the rubber-insulated it 
is rubber which acts as the non-conductor the quality 
of the compound is of special interest, for it must be 
capable of long service without cracking or hardening. 

Upon removal from the storage bins the rubber is 
washed, dried, compounded with sulphur and other in- 
gredients, milled, and sent to another storage room 
where it is aged a definite length of time. The charac- 
ter, experience and knowledge of the manufacturer are 
powerful factors in the intermediate processes — washing, 
drying, compounding, milling and ageing — that deter- 
mine, more than any other, the ultimate value of the 

155 



Rubber in Industry 

insulating material. Many "fillers" may be mixed 
with the rubber that unduly increase the weight and 
eventually destroy its dielectric value, thereby en- 
dangering life and property. To produce a good 
product, therefore, the inspectors, compounders and 
operators must be highly skilled, conscientious, and 
careful men; and the testing instruments and system 
must be so accurate as to eliminate the possibility of 
error. The preparation of the insulating material for 
"Goodrich" insulated wire conforms with our ideals of 
50 years' development and the same steps in an enor- 
mous yearly production of tires, belting, hose and 
thousands of other rubber articles. We, therefore, need 
not describe these steps more minutely. 

After thoroughly aged or seasoned, this compound is 
either applied directly to the wire by the tubing or 
insulating machines through the dies of which the wire 
is guided; or is first calendered and cut into strips of 
the proper thickness and width, then applied to the 
wire and cables by the strip process machines. The 
tubing and the strip or sheet processes constitute the 
two methods by which the rubber insulation is generally 
applied to wire, but there are many different compounds 
and thicknesses of rubber employed to meet various 
requirements. For instance, in automobile ignition 
wiring and storage battery feeder cables, special oil 
and acid resisting compounds must be used to meet the 
deteriorating effect of oils and acids upon rubber. 

The tubing machine method is employed principally 
on the smaller sizes of wire. By this method the com- 
pound is forced by the revolving worm through a die, 
surrounding the conductor with compound; the thick- 
ness of the wall being determined by the size of the 

156 



Rubber in Industry 

opening in the die. By this process the insulation is 
delivered without seams and in a homogeneous layer. 

By the strip process, which is more suitable for the 
larger wires and cables, the rubber wall is formed by 
folding one or two strips of compound around the con- 
ductor. Small wheels are engaged against the side of 
the cable which bind the edges of the strips together 
so effectively that, after vulcanization, the seams are as 
strong as other parts of the wall. 

Regardless, however, of the method the rubber com- 
pound is in a soft plastic condition and must be vulcan- 
ized to make it firm, elastic, permanent and enduring. 
Vulcanization is an essential feature in the manufacture 
of insulated wire and requires very careful attention, 
i.e., the duration of the treatment and the pressure used 
determine in a great measure the character of the 
finished product. A large percentage of the insulated 
wire which we produce goes directly from the insulating 
machinery to the vulcanizers. Some, however, es- 
pecially the larger cables, require reinforcement, ac- 
complished by winding upon it a layer or layers of tape 
which preserve the cylindrical form and prevent me- 
chanical injury of the still plastic insulation. In this 
connection we will explain that the tape once applied 
over the insulation is very seldom removed after the 
vulcanizing process is completed. In order that all 
parts of the rubber insulating walls may be subjected 
to a uniform temperature and pressure, the wire is 
wound on large drums or coiled spirally in circular 
pans. The live steam is therefore able to transmit its 
heat evenly to the whole surface of the insulation. 

Underwriter's Code. To insure that the public will be 
supplied with a quality which may be known as safe 

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Rubber in Industry 

for wiring buildings and for other general purposes, the 
National Association of Fire Underwriters has fixed cer- 
tain requirements that manufacturers must meet in 
order to offer a product approved by its Electrical Com- 
mittee; or which will be permitted to be used in all 
buildings upon which insurance is effective or may be 
written. These requirements are exacting; specifying 
among other things the quantity of rubber which must 
be contained in the insulation compound, and in order 
to avoid friction with the National Board, great care 
must be exercised in all manufacturing steps and at a 
considerable expense. These stringent requirements, 
however, not only protect the ultimate consumer but 
also react to the advantage of that class of manufac- 
turers of which The B. F. Goodrich Company is repre- 
sentative. In order to make their rulings effective the 
underwriters maintain a force of inspectors Who operate 
in conjunction with the testing laboratory at Chicago; 
i.e., these inspectors visit the wire manufacturer fre- 
quently and pick at random, from stock, samples to be 
tested. Furthermore, since it is required that the 
product of each manufacturer be distinctively marked, 
a piece or roll of wire may be taken from the stock of 
any jobber, dealer, or from an electrical contractor's 
job, sent to Chicago and subjected to the prescribed 
tests. In other words, the Underwriters may buy a 
roll or piece of wire anywhere and at any time and 
upon examination determine whose product it is. If 
the piece fails to pass even one phase of the test such 
failure is counted as a demerit against the manufacturer 
and the reader may be assured that the results of these 
tests are carefully recorded. Ten failures within any 
given six months result in the manufacturing privilege 

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Rubber in Industry 

with the approval of the National Board of Fire Un- 
derwriters, being withdrawn. The B. F. Goodrich 
Company is one of a group of six out of about thirty-five 
insulated wire manufacturers in the United States, who 
for the years 1915, 1916, 1917 and 1918 have enjoyed the 
distinction of not having a single demerit recorded 
against them. In fact the basic principles of quality of 
this company as applied to other products are here so 
strongly reflected that even in our cheapest grade, tests 
are nearly 100 per cent above the Underwriters' require- 
ments. 

Plain Rubber Covered. Although most insulated wire 
such as lamp and telephone cord, National Code inside 
and outside wire, etc., with which the lay public is 
more or less familiar, is generally finished over the in- 
sulation with a braided fabric jacket, either of cotton 
or silk, nevertheless, a large part of the wire sold es- 
pecially for installations where it may come in contact 
with acids or other agencies destructive to the fabric 
type of cover, is supplied only with a tough rubber 
casing or cover. As an instance where this is true we 
point to electric cable as used for the conveying of 
power to drills, etc., in mining service where the most 
severe conditions imaginable are met with. These 
cables are being constantly pulled over timber, rough 
floors and sharp rocks, bruised by falling rock, coal or 
ore and pinched by car wheels. Furthermore, mining 
cable is subjected to unusual wear by being wound onto 
and unwound from the carrying drums at frequent in- 
tervals and in spite of the care exercised by wire man- 
ufacturers generally in the construction of this service 
type the average life of mining cable prior to the intro- 
duction of the "Goodrich Standard Concentric" was but 

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Rubber in Industry 

two months. Today, however, we are constantly re- 
ceiving reports from large mines all over the world of a 
service of six, seven, and eight months' duration. 

"Goodrich Standard Concentric Mining Cable" is 
constructed by first insulating with rubber compound 
a very flexible stranded cable over which layer of rubber 
compound a frictioned fabric tape and braided fabric 
cover are next applied successively. Over this, the 
second conductor, composed of many wires, is applied 
helically, the whole then being covered with a tough, 
wear-resisting compound. To this description, we wish 
to add by way of explanation, a mention of the fact tlat 
after each layer of compound is applied to the cable a 
cure is effected, either on drums or in trays as previously 
described. 

Fabric Covered Wire. In addition to the plain, rub- 
ber-coverd type, considerable insulated wire is finished 
with a braided fabric cover or a combination cover of 
woven and braided fabric. When rubber impregnated 
woven fabric is used, such is always applied in tape 
form, being wound over the insulation in a helix with 
slightly overlapping edges. Should a second ply be re- 
quired this is wound over the first in like manner but 
in the contrary direction. No individual conductors 
protected with woven fabric covers alone are employed 
except when constituting a part of multiple conductor 
cable. This type is further protected over all by braided 
fabric jackets or lead sheathing. Braided fabric jackets 
are those which are constructed in tubular form directly 
over the insulation by the standard type of braiding 
machinery the same as employed in the construction of 
braided construction hose. As has been pointed out 
before this machine consists of a series of bobbins which 

160 






Rubber in Industry 

travel in an irregular circular path entwining the threads 
after the same manner in which a Maypole is wound, 
the wire in this case being the pole. 

Both cotton and silk are used in covering wire, the 
choice of material depending upon the service for which 
the finished product is desired, but the size of the thread 
and the number of bobbins employed must be deter- 
mined by the diameter of the conductor. This is to say, 
the larger the wire or cable the greater the number of 
bobbins and the coarser the thread. Beautiful variegated 
patterns or the underwriter's color scheme specifications 
for each manufacturer are secured by the employment 
of thread of contrasting colors, arranging the bobbins 
containing the different colors according to the pattern 
desired. 

Cotton covers either braided or taped, when exposed 
alternately to heat and moisture, that is, sunshine and 
rain, will deteriorate rapidly and therefore it is essential 
in order to preserve such coverings that they be treated 
with a moisture-proof compound. The Goodrich Com- 
pany uses for this purpose a special bituminous waxy 
preparation which thoroughly saturates the fabric cover, 
thereby rendering it waterproof. This is applied by 
passing the covered wires or cables through tanks where 
the wax is heated to liquid form. The surface is then 
polished by passing the wire or cable through a series 
of dies revolving rapidly in opposite directions. The 
compound which we use for proofing cotton covered 
wire, we may add, is distinctively Goodrich one par- 
ticular characteristic being that it will not stain the 
hands with a sticky, tarry substance as is so often the 
case with this type of wire. To this statement elec- 
tricians will testify. 

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Rubber in Industry 

Multiple Conductors. Gables composed of two or more 
individual conductors are frequently employed in sys- 
tems where many instruments are connected with one 
switchboard or similar device, as for example, in fire 
alarm, telegraph, and telephone service. These con- 
ductors may be separated from each other merely by a 
plain rubber insulation or may have in addition to the 
rubber insulation either a braided fabric taped jacket. 
There are many possible combinations in multiple con- 
ductors, but when two conductors only are desired, 
these are generally placed parallel both being encased 
in a braided fabric jacket. However, when three or 
more units are combined in one cable they are twisted 
together and one or more jackets braided over the 
whole construction. Cotton or jute filler is sometimes 
twisted in with the several units in order to fill up the 
spaces between them and to give the finished cable a 
smooth cylindrical appearance. 

To prevent error in "cable splicing" or in making con- 
nections to distributing racks without the necessity of 
employing testing devices each unit or pair in a multi- 
ple conductor cable, as the case may be, is usually 
covered with a braided jacket of distinctive coloring or 
color combination pattern after the manner described 
under the previous caption, Fabric Covered Wire. As 
will be recognized, this ingenious idea greatly facilitates 
the work of making a large number of connections 
where new cable is being installed. 

It is sometimes desirable that these fabric jackets be 
treated with a moisture-proof compound the same as 
wire employed in outside work, and at the same time 
not having the color contrasts destroyed as it would by 
the use of the black waterproof preparation. In such 

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Rubber in Industry 

instances a semi-transparent solution is used thus per- 
mitting the ready identification of the various wires or 
pairs and yet having the desired effect. The prepara- 
tion which we employ in this process is a characteristic- 
ally Goodrich formula and one which has proven to be 
a valuable asset particularly in the manufacture of 
automobile starting and lighting cable, telephone cable, 
etc. 

Where either single wire or multiple conductor cable 
with woven jacket covers is to be exposed to any con- 
siderable heat such as around drying machinery or in 
steel mills or where the fire hazard is particularly great 
the fabric covering is made fireproof either by the use 
of a fireproof paint or by asbestos fiber jackets, the 
choice depending upon installation conditions. 

Lead Covered Cable. It is frequently essential for tele- 
phone, telegraph, and even power and lighting cable, 
both for underground and aerial installations to be en- 
cased in a sheathing of lead. This type of electric con- 
ductor is not, however, as is often supposed, made by 
pulling the cable through a lead tube but on the con- 
trary, by forming the lead cover over the cable much 
after the same manner in which the outside rubber cover 
is applied to braided construction hose. In other words, 
the insulated wire or cable to be covered is passed 
through a machine receiving its sheathing of lead as it 
issues, a die governing the thickness and size. 

This machine is very similar to the one commonly 
employed in the manufacture of lead piping, being an 
enormously heavy combination furnace and force pump 
in which the lead is reduced to a flux and thereby forced 
out through the die over the cable by powerful hydraulic 
plungers which exert a constant pressure keeping 

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Rubber in Industry 

the wall thickness of the sheathing uniform. 
The mechanism of this machine is so arranged and con- 
structed that the lead coating is barely hot as it issues 
from the die, thereby doing no damage to the insulation 
or fabric covering underneath, besides being easily 
handled as it comes away from the die. 

Tests. Immediately following the vulcanization of all 
Goodrich rubber insulated wire two distinct electrical 
tests are made which most manufacturers, preferring to 
wait until the product has been finished, omit. Ex- 
perience, however, has demonstrated to us that these 
tests are responsible for a product nearer perfect than 
would otherwise be possible to maintain. The first of 
these tests is made to insure against leaks occurring in 
the insulation. Several hundred feet of wire in coils 
or bundles is immersed in a tank of water, all except 
the ends which are connected in multiple to the terminals 
of a high voltage circuit. After having remained under 
water for a certain length of time, the current is turned 
on and should there be a defect in the rubber wall, the 
soaking it receives will have made a path through 
which the high voltage current can escape. Thus, 
wherever the insulation has broken down, flashes or 
sparks will be observed springing from the surface of 
the wire. These spots are marked by the inspector and 
each coil, bundle, or single piece of wire containing even 
one leak, is rejected by him as imperfect and returned 
to the insulating department. Fortunately, leaks of 
this character may nearly always be repaired by simply 
replacing a section of the rubber insulation and vulcan- 
izing the patch built in on a small electric heater. All 
wire, however, after being repaired in this manner must 
again undergo the test. 

164 



Rubber in Industry 

The second test mentioned is conducted in order to 
determine the dielectric strength of the insulating com- 
pound and should the result of this test show any piece 
to fall below our standard, the whole coil will be re- 
jected as faulty and a subsequent investigation made in 
order to discover whether the weak resistance to the 
passage of current is due to low quality of ingredients 
used in the compound, under-milling of the compound, 
gritholes, or any one of several factors which might 
cause an insulation of low dielectric strength to be pro- 
duced. This test is made in a similar manner to the 
one previously described. 

Final tests according to the National Association of 
Fire Underwriters' requirements are also made after the 
wire or cable has been completed and is otherwise 
ready for shipment. These tests are of various kinds 
but made principally to determine electric and physical 
strengths of the insulation and a permanent record is 
kept in our factory office of the test of each coil, bundle, 
or piece of wire or cable produced, these being filled 
under serial numbers to correspond with numbers ap- 
pearing upon the tags attached to each bundle of wire. 
This system enables us to check up complaints should 
it be claimed that any particular shipment of ours had 
failed to meet the Underwriters' specifications. We are 
able immediately to turn to our records and secure a 
complete history of the tests made. 

Small conductors are shipped in bundles wrapped in 
paper tape to exclude light and dirt. Large conductors 
are wound on wooden reels, covered with paper and 
boxed in. Automatic devices are employed for coiling 
and wrapping, thus carrying out to the very last, prac- 
tices of economy in manufacture through the use of 

165 



Rubber in Industry 

which the savings in up-to-date production may be 
passed along to the ultimate consumer and thus the use 
of insulated wire be extended into every possible field. 

The Use of Insulated Wire. The duties of in- 
sulated wires are numerous and diversified; in fact, so 
multitudinous are the places where this product of the 
rubber factory plays a most vital part that a consider- 
able thesis might be prepared upon this subject alone. 
We, however, have not here the space to fully treat this 
phase of the wire question, if indeed a complete dis- 
cussion would be of value in a text of this kind; and 
accordingly, must confine ourselves to a mere outline 
of the topic leaving its development for further study 
and investigation on the part of our readers. 

To best exemplify our first statement, however, we 
may mention that rubber insulated wire forms an im- 
portant part of the construction of all modern buildings, 
is essential for starting and lighting systems of auto- 
mobiles, is indispensable to the safe operations of trains 
both within and without for the illumination of the 
coaches, for lighting the track ahead of the locomotive, 
and for the operation of the signals which guide the 
engineer safely over the maze of tracks and switches. 
Telephone, telegraph, and fire alarm systems are almost 
wholly dependent upon rubber insulated wire; the 
electric automobile would be useless without it and the 
conduction of high and low tension current for power 
purposes could not be accomplished without the use of 
some rubber insulated wire. Both mines and mills de- 
pend upon this useful article and the street car which 
transports the workman to and fro between their homes 
and the factories could not be operated if the electric cur- 

166 



Rubber in Industry 

rent could not enter the controller over protected con- 
ductors, while the army, the navy, and the merchant 
marine would today be hopelessly unable to cope with 
modern conditions of warfare and commerce without 
this very vital product. 

To better illustrate these assertions, we may mention 
that industry which interests The B. F. Goodrich Com- 
pany from so many standpoints, viz., the building of 
automobiles. This compact modern transportation unit 
which today is playing such an important part in our 
national and international life, would be useless without 
rubber insulated wire and although when compared to 
other items of rubber which enter into the construction 
of the automobile, wire in dollars and cents represents 
an infinitesimal outlay, it plays such an important part 
that its failure to deliver the service expected is of 
greater moment than even the performance of the rub- 
ber tires which all know to be indispensable. In other 
words, if the insulated electric wire does not properly 
conduct the current so as to explode the fuel charge in 
the cylinder of the gasoline driven car, or if it does not 
properly link the storage battery to the motor of an 
electric, all the tires in the world will not suffice to make 
these vehicles useful, for without "juice" they most 
surely must stand in their tracks until disintegration 
complete its work. 

Today the home without its electric lights, electric 
flatirons and vacuum cleaner attachments, seems to 
us to represent a page from the "Dark Ages;" the office 
without its telephone, its electrically driven adding ma- 
chine, multigraphing and tabulating devices, a decrepit 
institution and the community without its telephone 
and fire alarm system, a dismal if not dangerous place 

167 



Rubber in Industry 

in which to live. Thus we might continue through 
page after page of illustration, each portraying the ex- 
tent to which modern life is dependent upon insulated 
wire, particularly that of the rubber insulated type. 




168 



CHAPTER ELEVEN 

Marketing 

(Insulated Wire) 

SELLING. On the North American Continent today 
are some forty odd manufacturers of rubber insu- 
lated wire, about thirty-five of whom are located in the 
United States, where in addition to ourselves, there are 
approximately ten important manufacturers, that is, 
those who turn out a diversified high grade product. 
Considerable volume is, however, sold by the smaller 
companies, but many of these while marketing an 
extremely large footage, confine their output to the 
smaller sizes. As may be imagined, therefore, a 
diversity of selling methods exists, the policies of the 
different manufacturers necessarily varying according to 
the product, the volume of output, and the ideas of 
those in charge. Goodrich wire is marketed through an 
organization composed of men concerned solely with 
this one division of our output and who devote their 
whole time to selling this product. 

Channels of Distribution. The distribution of in- 
sulated wire from the Goodrich plant to the ultimate 
consumer is not accomplished through any set channel, 
but rather done according to the method which may be 
deemed best suited to the particular conditions of place, 
or division of product to be marketed. In other words, 
our distribution is accomplished partially through the 

169 



Rubber in Industry 

jobber, partially through the dealer, but frequently to 
the ultimate consumer direct. Why insulated wire 
must be so handled will be apparent when we call atten- 
tion to its wide diversity of uses. But told in other 
words, insulated wire is used in the lighting systems of 
buildings could not be sold to the consumer direct 
with economy, and therefore must be distributed either 
through the jobber, dealer, or electrical contractor, and 
since the jobber offers the most logical medium through 
which to distribute this item, he, in most cases, is em- 
ployed. 

On the other hand, signal cable, submarine cable, 
generator cable or telephone cable can better be sold 
direct to the users of such wires or to the manufacturers of 
electrical devices, while automobile starting and lighting 
cable, on account of the special specifications to be 
met, must be sold to the consumer, i.e., manufacturer 
of automobiles. Therefore, those traveling in the in- 
terest of insulated wire sales must visit all classes of 
trade, such as jobbers and dealers in wire and electrical 
goods, steam and electric railroads, automobile manu- 
facturers, telephone and telegraph companies, manu- 
facturers of fire alarm systems, municipalities, archi- 
tects, etc. In some instances it may be wise for us to 
give exclusive selling territories to the jobbing trade for 
certain items of our line, whereas, under other con- 
ditions it may be best to secure the business on an 
open market basis. This paragraph, however, must not 
be taken as a declaration of Goodrich selling policies 
but merely as an indication showing the methods which 
we must ordinarily employ in the distribution of our 
insulated wire output. 

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Rubber in Industry 

Branch Stocks. In certain sections of the country 
where industrial conditions demand such an arrange- 
ment, in order to facilitate deliveries, our established 
branches carry in stock such items of the insulated wire 
line as have been found most in demand by the industries 
located in their respective territories. The advantages 
to the trade and consumer of having such local sources 
of supply from which quick deliveries may be made, 
will be readily apparent to our readers and we, therefore, 
need dwell upon the subject no further than to mention 
that such stocks permit the filling of orders with the 
least possible delay. 

It is our intent to have these stocks complete enough 
at all times to fill every reasonable immediate shipment 
order. The branches which at present are carrying 
stocks of insulated wire are New York, Detroit, and 
Chicago. These are assigned a definitely bounded terri- 
tory which they serve and the balance of the country 
is served direct by Akron. 



171 



Rubber in Industry 

Conclusion. It is a strange coincidence that two 
factors — electricity and rubber — about the exact nature 
of which so little is known, should be closely associated 
in the production of a common commodity — insulated 
wire. As the scientists Gray, Volta, Ohm, Henry, 
Faraday, Edison and Westinghouse analyzed the con- 
ditions governing the manifestations of electricity and 
developed means for making its force useful; so did 
Peal, Macintosh, Priestly, Goodyear, and Goodrich 
apply themselves to the problem of converting the soft 
unstable crude rubber into the enduring form in which 
it now so satisfactorily meets the requirements of the 
civilized world. The high quality of the Goodrich prod- 
uct entitles our wire to its excellent reputation, and 
also justifies the share which we possess in the leader- 
ship of the industry. 



172 



Review Questions 



Belting, Hose, Molded Goods, Packing, Mats, 

Tiling, and Miscellaneous Mechanical 

Rubber Items 

PREFACE 

1. In a general way, what articles are included under 
Mechanical Goods? 

2. What article was the first production of the Good- 
rich Company and how branded? 

3. Name the divisions of Mechanical Goods which we 
employ in factory and sales activities. 

CHAPTER ONE 

1 . Discuss briefly the history of belting showing why 
rubber belting entered the field. 

2. Describe the construction of a rubber belt, giving 
special attention to vulcanization. 

3. Why do we market several brands of transmission 
belts? 

4. Name and describe three types of Rubber Trans- 
mission Belts. 

5. Discuss troughing qualities, cover and edges of our 
Conveyor Belts. 

6. Describe the step-ply construction as sometimes 
used in Conveyor Belt construction, showing its 
disadvantage. 

7. Name at least two belts which we offer for special 
work. 

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Rubber in Industry 

8. What characteristics must Elevator Belt construc- 
tion include and why? 

CHAPTER TWO 

1. Give a brief history of hose. 

2. Describe the Wrapped Duck construction Hose. 

3. What are the features of Braided Reel Hose that 
explain its rapid acceptance by users? 

4. Compare or contrast the building up of Woven and 
Braided Hose. 

5. Discuss the types and application of Protective Cov- 
erings. 

6. Explain the difference between Water and Garden 
Hose. 

7. What is the chief difficulty to overcome when con- 
structing Steam Hose? 

8. Name at least five uses for hose which require 
special constructions. 

9. Tell in 100 words why we may be termed Hose 
Specialists. 

CHAPTER THREE 

1. Where and by whom were the first molds used to 
make rubber articles? 

2. What products, generally speaking, are included 
under Molded and Lathe-Cut Goods? 

3. Describe the steps in the construction of any molded 
article. 

4. Why do we ourselves make nearly all the molds 
used in our Molded Department? 

h. What rank do we hold in Valve Manufacture and 
why? 

174 



Rubber in Industry 

6. What is meant by Spring Rubber and where is it 
used? 

7. Describe at least three different styles used in the 
construction of Billiard Cushions? 

8. Is "Textan" a rubber sole? Explain. 

9. Write a paragraph on "Molded and Lathe-Cut 
Goods Constitute the Made-to-Order Department 
of Rubber Manufacture." 

CHAPTER FOUR 

1. Describe the use of packing. 

2. Give a short synopsis of packing evolution. 

3. How is sheet packing manufactured? 

4. Define: — Sheet Packing, Hydraulic Packing, and 
Spiral Packing. 

o. How is Hydraulic Packing made? 

6. Why is cloth sometimes placed in Sheet Packing? 

7. What do we use for lubricating packing and for 
what purpose is this substance applied? 

8. What special features do we sometimes employ in 
Sheet Packing constructions? 

9. Do we consider our present lineup of Packings the 
"last word" in this field? 

10. When excessive oil is present, what Packing do we 
recommend? 

CHAPTER FIVE 

What characteristics has rubber to warrant its ap- 
plication as a flooring or floor covering? 

2. Give a few of the more common uses for Perforated 
Mats. 

3. Describe the construction of a Perforated Mat. 

175 



Rubber in Industry 

4. Compare or contrast Perforated Mats and Solid 
Matting. 

5. Discuss Fabric Insertion in Solid Matting. 

6. Name at least three special solid mats we offer. 

7. Where has Interlocking Tiling found its chief appli- 
cation? 

8. Describe construction of Interlocking Tiling. 

9. How do we recommend the laying of our Inter- 
locking Tiling? 

10. Describe the construction and appearance of our 
Inlaid Tiling. 

CHAPTER SIX 

1. What articles constitute the miscellaneous group? 

2. Who invented Rubber Thread and why? 

3. Name three or more present day uses for Rubber 
Thread. 

4. Describe how we make Rubber Thread. 

5. Our Rubber Rolls are used chiefly in connection 
with what appliances? 

6. How do we make rolls? 

7. Describe the building up of a Deckle Strap and 
show the advantage of our method. 

8. Where is Glazing Rubber used? 

9. Are the places for the use of Channel Rubber de- 
creasing? Explain your answer. 

CHAPTER SEVEN 

1. Through what mediums do Mechanical Goods rep- 
resentatives market our products? 

2. Explain fully what connection a salesman traveling 
in Chicago territory has with the head of Me- 
chanical Sales at Akron. 

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Rubber in Industry 

3. Where are stocks of Mechanical Goods maintained 
and why? 

4. What protection does a buyer have when selecting 
an article manufactured in our factory? 

REVIEW QUESTIONS 
Insulated Wire 

CHAPTER EIGHT 

1. What is polarity? 

2. What is the relationship between magnetism and 
electricity? 

3. What commercial apparatus is based on the dis- 
coveries of Henry and Faraday? 

4. Name the two sources from which current elec- 
tricity may be derived. Which is the more im- 
portant and why? 

5. Describe in your own words, the principles of: — 
the battery cell; the dynamo or generator. 

6. What is meant by the terms: — direct current; al- 
ternating current; circuit; volt; ampere; resistance; 
watt; kilowatt? 

7. Why do most of the greater transmission lines 
transmit alternating current only? 

8. What is the difference between a primary battery 
and a storage battery? 

9. Name the two principal types of storage batteries 
and differentiate between them. 

10. Who discovered that electricity may be conducted 
from one point to another? How? 

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CHAPTER NINE 

1. Name the six best conductors of electricity. 

2. State why copper is more generally employed than 
any of the other five and describe its advantages 
over the others, individually. 

3. Whose discoveries and inventions lead to the 
present enormous demand for insulated wire? 

4. Why are two wires necessary in connecting up 
lamps, motors or any other electrical devices? 

5. Name our principal copper producing states and 
mention four mines. 

6. Where and when was the first copper mine opened 
in the United States? 

7. Explain the principal step in the process of obtain- 
ing copper wire bars from the earth. 

8. Describe electrolytic refining. 

9. Explain the various processes employed to convert 
the wire bars into finely graduated wire ready to 
be insulated. 

10. Which is the larger; a number wire or a number 
10 wire? 

CHAPTER TEN 

1. What is the name of the principal wire gauge used 
in this country, and who is it manufactured by? 

2. What is the size of a wire whose cross-sectional 
area and conductivity is twice as great as a num- 
ber 10 wire? State the rule. 

3. What is meant by a circular mil? 

4. Why is stranded wire used instead of solid wire in 
the manufacture of large cables? 

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Rubber in Industry 

5. What is the best insulator or dielectric? Name 
four which have greater dielectric value than vul- 
canized rubber and compare each with vulcanized 
rubber. 

6. What is the most important ingredient which is 
used with rubber in the manufacture of insulating 
material? 

7. Why is it necessary to "tin" the wire before apply- 
ing rubber insulation? 

8. What properties should a good insulator (non- 
conductor) embody? 

9. Describe the processes which are employed in the 
application of the insulation to the wire and explain 
the various tests that are employed in the. manu- 
facture of "Goodrich" Insulated Wire. 

10. In multiple conductor cables, why are different 
color combinations used in braiding the various 
wires which go to make up the cable? 

CHAPTER ELEVEN 

1. What is meant by the Underwriters' Code? 

2. Describe the inspection methods of the Fire Under- 
writers. 

3. How does the inspector identify the manufacturer 
of a piece of wire when it bears no label? 

4. Explain the effect of the inspections on the manu- 
facturer. 

5. Explain a particular distinction which The B. F. 
Goodrich Company enjoys among the wire manu- 
facturers. 

6. Describe the different methods of marketing wire. 

7. Give an outline of your idea of a better insulated 
wire selling plan. 

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Industry 



8. When and by whom was The B. F. Goodrich Com- 
pany organized? 

9. Tell as much of the history and development of the 
company as you can. 

10. What do you think of the future of the Rubber In- 
dustry? 




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LIBRARY OF CONGRESS 

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